Antidepressants are a class of
medication
A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...
used to treat
major depressive disorder
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introdu ...
,
anxiety disorder
Anxiety disorders are a cluster of mental disorders characterized by significant and uncontrollable feelings of anxiety and fear such that a person's social, occupational, and personal function are significantly impaired. Anxiety may cause physi ...
s,
chronic pain
Chronic pain is classified as pain that lasts longer than three to six months. In medicine, the distinction between Acute (medicine), acute and Chronic condition, chronic pain is sometimes determined by the amount of time since onset. Two commonly ...
conditions, and to help manage
addiction
Addiction is a neuropsychological disorder characterized by a persistent and intense urge to engage in certain behaviors, one of which is the usage of a drug, despite substantial harm and other negative consequences. Repetitive drug use o ...
s.
Common
side-effects
In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...
of antidepressants include
dry mouth
Xerostomia, also known as dry mouth, is dryness in the mouth, which may be associated with a change in the composition of saliva, or reduced salivary flow, or have no identifiable cause.
This symptom is very common and is often seen as a side eff ...
,
weight gain
Weight gain is an increase in body weight. This can involve an increase in muscle mass, fat deposits, excess fluids such as water or other factors. Weight gain can be a symptom of a serious medical condition.
Description
Weight gain occurs wh ...
,
dizziness
Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to disequilibrium or a non-specific feeling, such as giddiness or foolishness.
Dizziness is a common medical c ...
,
headache
Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches.
Headaches can occur as a result ...
s,
sexual dysfunction
Sexual dysfunction is difficulty experienced by an individual or partners during any stage of normal sexual activity, including physical pleasure, desire, preference, arousal, or orgasm. The World Health Organization defines sexual dysfunction as ...
,
and
emotional blunting
Reduced affect display, sometimes referred to as emotional blunting or emotional numbing, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings ( affect display) either verbally or nonverba ...
. There is a slight increased risk of suicidal thinking and behavior when taken by children, adolescents, and young adults.
Discontinuation syndrome may occur after stopping any antidepressant which resembles recurrent depression.
Some research regarding the effectiveness of antidepressants for depression in adults has found benefits,
whilst other research has not.
Evidence of benefit in children and adolescents is unclear.
The twenty-one most commonly prescribed antidepressant medications are more effective than placebo for the short-term (acute) treatments of adults with
major depressive disorder
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introdu ...
.
There is debate in the
medical community about how much of the observed effects of antidepressants can be attributed to the
placebo
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures.
In general ...
effect, with some claiming that there is no effect above and beyond it.
Research about the work effectiveness of antidepressants drugs is done on people that have very severe symptoms. This population exhibits much weaker placebo responses, meaning that the result cannot be extrapolated to the general population.
There are also several other effective treatments for depression which do not involve medications, or may be used in conjunction with medications.
Medical uses
Antidepressants are prescribed to treat
major depressive disorder
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introdu ...
(MDD),
anxiety disorder
Anxiety disorders are a cluster of mental disorders characterized by significant and uncontrollable feelings of anxiety and fear such that a person's social, occupational, and personal function are significantly impaired. Anxiety may cause physi ...
s,
chronic pain
Chronic pain is classified as pain that lasts longer than three to six months. In medicine, the distinction between Acute (medicine), acute and Chronic condition, chronic pain is sometimes determined by the amount of time since onset. Two commonly ...
, and some addictions. Antidepressants are often used in combinations with one another.
The proponents of the monoamine hypothesis of depression recommend choosing the antidepressant with the mechanism of action impacting the most prominent symptoms—for example, they advocate that people with MDD who are also anxious or irritable should be treated with
SSRI
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracellul ...
s or
norepinephrine reuptake inhibitor
A norepinephrine reuptake inhibitor (NRI, NERI) or noradrenaline reuptake inhibitor or adrenergic reuptake inhibitor (ARI), is a type of drug that acts as a reuptake inhibitor for the neurotransmitters norepinephrine (noradrenaline) and epineph ...
s, while people suffering from a loss of energy and enjoyment of life should take with norepinephrine and dopamine enhancing drugs.
Major depressive disorder
The UK
National Institute for Health and Care Excellence
The National Institute for Health and Care Excellence (NICE) is an executive non-departmental public body of the Department of Health and Social Care in England that publishes guidelines in four areas:
* the use of health technologies withi ...
(NICE) 2009 guidelines indicate that antidepressants should not be routinely used for the initial treatment of mild depression. This is due to the risk to benefit ratio being deemed as poor. The guidelines recommended that antidepressant treatment be considered for the following:
* For people with a history of moderate or severe depression
* For people with mild depression that has been present for a long period of time
* As a first-line treatment for moderate to severe depression
* As a second-line treatment for mild depression that persists after other interventions
The guidelines further note that in most cases, antidepressant treatment should be used in combination with psychosocial interventions, should be continued for at least six months to reduce the risk of relapse, and that
selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracell ...
(SSRIs) are typically better tolerated than other antidepressants.
American Psychiatric Association
The American Psychiatric Association (APA) is the main professional organization of psychiatrists and trainee psychiatrists in the United States, and the largest psychiatric organization in the world. It has more than 37,000 members are involve ...
treatment guidelines recommend that initial treatment be individually tailored based on certain factors including severity of symptoms, co-existing disorders, prior treatment experience, and the person's preference. Options may include pharmacotherapy, psychotherapy, electroconvulsive therapy (ECT),
transcranial magnetic stimulation
Transcranial magnetic stimulation (TMS) is a noninvasive form of brain stimulation in which a changing magnetic field is used to induce an electric current at a specific area of the brain through electromagnetic induction. An electric pulse gener ...
(TMS) or light therapy. They recommended antidepressant medication as an initial treatment choice in people with mild, moderate, or severe major depression, that should be given to all people with severe depression unless ECT is planned.
Reviews of antidepressants generally find that they benefit adults with depression.
On the other hand, some contend that most studies on antidepressant medication are confounded by several biases: the lack of an
active placebo An active placebo is a placebo that produces noticeable side effects that may convince the person being treated that they are receiving a legitimate treatment, rather than an ineffective placebo.
Nomenclature
According to a 1965 paper, the term " ...
, which means that many people in the placebo arm of a
double-blind study
In a blind or blinded experiment, information which may influence the participants of the experiment is withheld until after the experiment is complete. Good blinding can reduce or eliminate experimental biases that arise from a participants' expec ...
may figure out that they are not getting any true treatment, thus destroying double-blindness; a short follow up after termination of treatment; non-systematic recording of adverse effects; very strict exclusion criteria in samples of patients; studies being paid for by the industry; selective publication of results. This means that the small beneficial effects that are found may not be statistically significant.
[
Among the twenty-one most commonly prescribed antidepressants, the most effective and well-tolerated seem to be ]Escitalopram
Escitalopram, sold under the brand names Lexapro and Cipralex, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. Escitalopram is mainly used to treat major depressive disorder and generalized anxiet ...
, Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
, Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
, Agomelatine
Agomelatine, sold under the brand names Valdoxan and Thymanax, among others, is an atypical antidepressant most commonly used to treat major depressive disorder and generalized anxiety disorder. One review found that it is as effective as other a ...
, and Mirtazapine
Mirtazapine, sold under the brand name Remeron amongst others, is an atypical antidepressant, and as such is used primarily to treat depression. Its effects may take up to four weeks, but can also manifest as early as one to two weeks. It is o ...
. As for children and adolescents with moderate-to-severe depressive disorder, Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
seems to be the best treatment (either with or without cognitive behavioural therapy
Cognitive behavioral therapy (CBT) is a psycho-social intervention that aims to reduce symptoms of various mental health conditions, primarily depression and anxiety disorders. CBT focuses on challenging and changing cognitive distortions (su ...
) but more research is needed to be certain. Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
, Escitalopram
Escitalopram, sold under the brand names Lexapro and Cipralex, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. Escitalopram is mainly used to treat major depressive disorder and generalized anxiet ...
, and Duloxetine
Duloxetine, sold under the brand name Cymbalta among others, is a medication used to treat major depressive disorder, generalized anxiety disorder, fibromyalgia, neuropathic pain and central sensitization. It is taken by mouth. It is a serotoni ...
might also help in reducing symptoms.
Anxiety disorders
For children and adolescents, Fluvoxamine
Fluvoxamine, sold under the brand name Luvox and Faverin among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is primarily used to treat major depressive disorder and obsessive–compulsive disorder ...
is effective in treating a range of anxiety disorders. Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
, Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
and Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
can also help with managing various forms of anxiety in children and adolescents.
Generalized anxiety disorder
Antidepressants are recommended by the National Institute for Health and Care Excellence (NICE) for the treatment of generalized anxiety disorder
Generalized anxiety disorder (GAD) is a mental and behavioral disorder, specifically an anxiety disorder characterized by excessive, uncontrollable and often irrational worry about events or activities. Worry often interferes with daily function ...
(GAD) that has failed to respond to conservative measures such as education and self-help activities. GAD is a common disorder of which the central feature is excessively worrying about a number of different events. Key symptoms include excessive anxiety about multiple events and issues, and difficulty controlling worrisome thoughts that persists for at least 6 months.
Antidepressants provide a modest-to-moderate reduction in anxiety in GAD. The efficacy of different antidepressants is similar.
Social anxiety disorder
Some antidepressants are used as a treatment for social anxiety disorder
Social anxiety disorder (SAD), also known as social phobia, is an anxiety disorder characterized by sentiments of fear and anxiety in social situations, causing considerable distress and impaired ability to function in at least some aspects ...
, but their efficacy is not entirely convincing, as only a small proportion of antidepressants showed some efficacy for this condition. Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
was the first drug to be FDA-approved for this disorder. Its efficacy is considered beneficial, although not everyone responds favorably to the drug. Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
and Fluvoxamine
Fluvoxamine, sold under the brand name Luvox and Faverin among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is primarily used to treat major depressive disorder and obsessive–compulsive disorder ...
extended release were later approved for it as well, while Escitalopram
Escitalopram, sold under the brand names Lexapro and Cipralex, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. Escitalopram is mainly used to treat major depressive disorder and generalized anxiet ...
is used off-label
Off-label use is the use of pharmaceutical drugs for an unapproved indication or in an unapproved age group, dosage, or route of administration. Both prescription drugs and over-the-counter drugs (OTCs) can be used in off-label ways, although ...
with acceptable efficacy. However, there isn't enough evidence to support Citalopram
Citalopram, sold under the brand name Celexa among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive compulsive disorder, panic disorder, and socia ...
for treating social anxiety disorder, and Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
was no better than a placebo in clinical trials. SSRI
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracellul ...
s are used as a first-line treatment for social anxiety, but they don't work for everyone. One alternative would be Venlafaxine
Venlafaxine, sold under the brand name Effexor among others, is an antidepressant medication of the serotonin-norepinephrine reuptake inhibitor (SNRI) class. It is used to treat major depressive disorder, generalized anxiety disorder, panic di ...
, which is a SNRI. It showed benefits for social phobia in five clinical trials against placebo, while the other SNRIs are not considered particularly useful for this disorder as many of them didn't undergo testing for it. , it is unclear if Duloxetine
Duloxetine, sold under the brand name Cymbalta among others, is a medication used to treat major depressive disorder, generalized anxiety disorder, fibromyalgia, neuropathic pain and central sensitization. It is taken by mouth. It is a serotoni ...
and Desvenlafaxine can provide benefits for people with social anxiety. However, another class of antidepressants called MAOI
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especi ...
s are considered effective for social anxiety, but they come with many unwanted side effects and are rarely used. Phenelzine
Phenelzine, sold under the brand name Nardil, among others, is a non-selective and irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class which is primarily used as an antidepressant and anxiolytic. Along with tranylcypromine and ...
was shown to be a good treatment option, but its use is limited by dietary restrictions. Moclobemide
Moclobemide, sold under the brand names Amira, Aurorix, Clobemix, Depnil and Manerix among others, is a reversible inhibitor of monoamine oxidase A (RIMA) drug primarily used to treat depression and social anxiety. It is not approved for use in t ...
is a RIMA
Rima, also known as Rima the Jungle Girl, is the fictional heroine of W. H. Hudson's 1904 novel '' Green Mansions: A Romance of the Tropical Forest''. In it, Rima, a primitive girl of the shrinking rain forest of South America, meets Abel, a pol ...
and showed mixed results, but still received approval in some European countries for social anxiety disorder. TCA antidepressants, such as Clomipramine
Clomipramine, sold under the brand name Anafranil among others, is a tricyclic antidepressant (TCA). It is used for the treatment of obsessive–compulsive disorder, panic disorder, major depressive disorder, and chronic pain. It may increase th ...
and Imipramine
Imipramine, sold under the brand name Tofranil, among others, is a tricyclic antidepressant (TCA) mainly used in the treatment of depression. It is also effective in treating anxiety and panic disorder. The drug is also used to treat bedwetting. ...
, are not considered effective for this anxiety disorder in particular. This leaves out SSRIs such as Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
, Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
and Fluvoxamine
Fluvoxamine, sold under the brand name Luvox and Faverin among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is primarily used to treat major depressive disorder and obsessive–compulsive disorder ...
CR as acceptable and tolerated treatment options for this disorder.
Obsessive–compulsive disorder
SSRIs
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracellul ...
are a second-line treatment of adult obsessive–compulsive disorder
Obsessive–compulsive disorder (OCD) is a mental and behavioral disorder in which an individual has intrusive thoughts and/or feels the need to perform certain routines repeatedly to the extent where it induces distress or impairs general ...
(OCD) with mild functional impairment, and as first-line treatment for those with moderate or severe impairment.
In children, SSRIs are considered as a second-line therapy in those with moderate-to-severe impairment, with close monitoring for psychiatric adverse effects. Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
and Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
are effective in treating OCD for children and adolescents.
Clomipramine
Clomipramine, sold under the brand name Anafranil among others, is a tricyclic antidepressant (TCA). It is used for the treatment of obsessive–compulsive disorder, panic disorder, major depressive disorder, and chronic pain. It may increase th ...
, a TCA drug, is considered effective and useful for OCD. However, it is used as a second-line treatment because it is less well-tolerated than the SSRIs. Despite this, it has not shown superiority to Fluvoxamine
Fluvoxamine, sold under the brand name Luvox and Faverin among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is primarily used to treat major depressive disorder and obsessive–compulsive disorder ...
in trials. All SSRIs can be used effectively for OCD. SNRI use may also be attempted, though no SNRIs have been approved for treatment of OCD. Despite these treatment options, many patients remain symptomatic after initiating the medication, and less than half achieve remission.
Post traumatic stress disorder
Antidepressants are one of the treatment options for PTSD
Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on a ...
. However, their efficacy is not well established. Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
and Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
, both of the SSRI
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracellul ...
class, have been FDA approved for the treatment of PTSD. Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
has slightly higher response and remission rates than sertraline for this condition. However, neither drug is considered very helpful for a broad patient demographic. Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
and Venlafaxine
Venlafaxine, sold under the brand name Effexor among others, is an antidepressant medication of the serotonin-norepinephrine reuptake inhibitor (SNRI) class. It is used to treat major depressive disorder, generalized anxiety disorder, panic di ...
are used off-label. Fluoxetine has produced unsatisfactory mixed results. Venlafaxine showed response rates of 78%, which is significantly higher than what paroxetine and sertraline achieved. However, it did not address as many symptoms of PTSD as Paroxetine and Sertraline, in part due to the fact the Venlafaxine is an SNRI. This class of drugs inhibits the reuptake of Norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
, which may cause anxiety in some patients. Fluvoxamine
Fluvoxamine, sold under the brand name Luvox and Faverin among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is primarily used to treat major depressive disorder and obsessive–compulsive disorder ...
, Escitalopram
Escitalopram, sold under the brand names Lexapro and Cipralex, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. Escitalopram is mainly used to treat major depressive disorder and generalized anxiet ...
and Citalopram
Citalopram, sold under the brand name Celexa among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive compulsive disorder, panic disorder, and socia ...
were not well tested in this disorder. MAOI
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especi ...
s, while some of them may be helpful, are not used much because of their unwanted side effects. This leaves paroxetine and sertraline as acceptable treatment options for some people, although more effective antidepressants are needed.
Panic disorder
Panic disorder
Panic disorder is a mental disorder, mental and Abnormal behavior, behavioral disease#Disorder, disorder, specifically an anxiety disorder characterized by reoccurring unexpected panic attacks. Panic attacks are sudden periods of intense fear th ...
is treated relatively well with medications compared to other disorders. Several classes of antidepressants have shown efficacy for this disorder, with SSRIs and SNRIs used first-line. Paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
, Sertraline
Sertraline, sold under the brand name Zoloft among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. The efficacy of sertraline for depression is similar to that of other antidepressants, and the differe ...
, Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
are FDA approved for panic disorder, while fluvoxamine, escitalopram and citalopram are also considered effective for it. The SNRI venlafaxine is also approved for this condition. Unlike with social anxiety
Social anxiety is the anxiety and fear specifically linked to being in social settings (i.e., interacting with others). Some categories of disorders associated with social anxiety include anxiety disorders, mood disorders, autism spectrum disord ...
and PTSD
Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on a ...
, some TCAs antidepressants, like Clomipramine
Clomipramine, sold under the brand name Anafranil among others, is a tricyclic antidepressant (TCA). It is used for the treatment of obsessive–compulsive disorder, panic disorder, major depressive disorder, and chronic pain. It may increase th ...
and Imipramine
Imipramine, sold under the brand name Tofranil, among others, is a tricyclic antidepressant (TCA) mainly used in the treatment of depression. It is also effective in treating anxiety and panic disorder. The drug is also used to treat bedwetting. ...
have shown efficacy for panic disorder. Moreover, the MAOI
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especi ...
Phenelzine
Phenelzine, sold under the brand name Nardil, among others, is a non-selective and irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class which is primarily used as an antidepressant and anxiolytic. Along with tranylcypromine and ...
is also considered useful. Panic disorder has many drugs for its treatment. However, the starting dose must be lower than the one used for major depressive disorder because people have reported an increase in anxiety as a result of starting the medication. In conclusion, while panic disorder's treatment options seem acceptable and useful for this condition, many people are still symptomatic after treatment with residual symptoms.
Eating disorders
Antidepressants are recommended as an alternative or additional first step to self-help programs in the treatment of bulimia nervosa
Bulimia nervosa, also known as simply bulimia, is an eating disorder characterized by binge eating followed by purging or fasting, and excessive concern with body shape and weight. The aim of this activity is to expel the body of calories eate ...
. SSRIs (fluoxetine in particular) are preferred over other antidepressants due to their acceptability, tolerability, and superior reduction of symptoms in short-term trials. Long-term efficacy remains poorly characterized. Bupropion
Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the case ...
is not recommended for the treatment of eating disorders, due to an increased risk of seizure.
Similar recommendations apply to binge eating disorder
Binge eating disorder (BED) is an eating disorder characterized by frequent and recurrent binge eating episodes with associated negative psychological and social problems, but without the compensatory behaviors common to bulimia nervosa, OSFED, o ...
. SSRIs provide short-term reductions in binge eating behavior, but have not been associated with significant weight loss.
Clinical trials have generated mostly negative results for the use of SSRIs in the treatment of anorexia nervosa
Anorexia nervosa, often referred to simply as anorexia, is an eating disorder characterized by low weight, food restriction, body image disturbance, fear of gaining weight, and an overpowering desire to be thin. ''Anorexia'' is a term of Gr ...
. Treatment guidelines from the National Institute of Health and Care Excellence (NICE) recommend against the use of SSRIs in this disorder. Those from the American Psychiatric Association (APA) note that SSRIs confer no advantage regarding weight gain, but may be used for the treatment of co-existing depressive, anxiety, or obsessive–compulsive disorders.
Pain
Fibromyalgia
A 2012 meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...
concluded that antidepressants treatment favorably affects pain, health-related quality of life, depression, and sleep in fibromyalgia
Fibromyalgia (FM) is a medical condition defined by the presence of chronic widespread pain, fatigue, waking unrefreshed, cognitive symptoms, lower abdominal pain or cramps, and depression. Other symptoms include insomnia and a general hyp ...
syndrome. Tricyclics
Tricyclics are chemical compounds that contain three interconnected rings of atoms.
Many compounds have a tricyclic structure, but in pharmacology, the term has traditionally been reserved to describe heterocyclic drugs. Among these are ant ...
appear to be the most effective class, with moderate effects on pain and sleep, and small effects on fatigue and health-related quality of life. The fraction of people experiencing a 30% pain reduction on tricyclics was 48%, versus 28% on placebo. For SSRIs and SNRIs, the fractions of people experiencing a 30% pain reduction were 36% (20% in the placebo comparator arms) and 42% (32% in the corresponding placebo comparator arms) respectively. Discontinuation of treatment due to side effects was common. Antidepressants including Amitriptyline
Amitriptyline, sold under the brand name Elavil among others, is a tricyclic antidepressant primarily used to treat cyclic vomiting syndrome (CVS), major depressive disorder and a variety of pain syndromes from neuropathic pain to fibromyalgi ...
, Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
, Duloxetine
Duloxetine, sold under the brand name Cymbalta among others, is a medication used to treat major depressive disorder, generalized anxiety disorder, fibromyalgia, neuropathic pain and central sensitization. It is taken by mouth. It is a serotoni ...
, Milnacipran
Milnacipran (trade names Ixel, Savella, Dalcipran, Toledomin) is a serotonin–norepinephrine reuptake inhibitor (SNRI) used in the clinical treatment of fibromyalgia. It is not approved for the clinical treatment of major depressive disorder in ...
, Moclobemide
Moclobemide, sold under the brand names Amira, Aurorix, Clobemix, Depnil and Manerix among others, is a reversible inhibitor of monoamine oxidase A (RIMA) drug primarily used to treat depression and social anxiety. It is not approved for use in t ...
, and Pirlindole
Pirlindole (Lifril, Pyrazidol) is mainly a reversible inhibitor of monoamine oxidase A (RIMA) and secondly a SNRI which was developed and is used in Russia as an antidepressant. It is structurally and pharmacologically related to metralindole. ...
are recommended by the European League Against Rheumatism (EULAR) for the treatment of fibromyalgia based on "limited evidence".
Neuropathic pain
A 2014 meta-analysis from the Cochrane Collaboration
Cochrane (previously known as the Cochrane Collaboration) is a British international charitable organisation formed to organise medical research findings to facilitate evidence-based choices about health interventions involving health profess ...
found the antidepressant Duloxetine
Duloxetine, sold under the brand name Cymbalta among others, is a medication used to treat major depressive disorder, generalized anxiety disorder, fibromyalgia, neuropathic pain and central sensitization. It is taken by mouth. It is a serotoni ...
to be effective for the treatment of pain resulting from diabetic neuropathy
Diabetic neuropathy is various types of nerve damage associated with diabetes mellitus. Symptoms depend on the site of nerve damage and can include motor changes such as weakness; sensory symptoms such as numbness, tingling, or pain; or autonomic c ...
. The same group reviewed data for Amitriptyline
Amitriptyline, sold under the brand name Elavil among others, is a tricyclic antidepressant primarily used to treat cyclic vomiting syndrome (CVS), major depressive disorder and a variety of pain syndromes from neuropathic pain to fibromyalgi ...
in the treatment of neuropathic pain
Neuropathic pain is pain caused by damage or disease affecting the somatosensory system. Neuropathic pain may be associated with abnormal sensations called dysesthesia or pain from normally non-painful stimuli (allodynia). It may have continuous ...
and found limited useful randomized clinical trial data. They concluded that the long history of successful use in the community for the treatment of fibromyalgia and neuropathic pain justified its continued use. The group was concerned about the potential overestimation for the amount of pain relief provided by amitriptyline, and highlighted that only a small number of people will experience significant pain relief by taking this medication.
Other uses
Antidepressants may be modestly helpful for treating people who have both depression and alcohol dependence, however the evidence supporting this association is of low quality. Bupropion
Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the case ...
is used to help people stop smoking. Antidepressants are also used to control some symptoms of narcolepsy
Narcolepsy is a long-term neurological disorder that involves a decreased ability to regulate sleep–wake cycles. Symptoms often include periods of excessive daytime sleepiness and brief involuntary sleep episodes. About 70% of those affec ...
. Antidepressants may be used to relieve pain in people with active rheumatoid arthritis
Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and hands are involv ...
. However, further research is required. Antidepressants have been shown to be superior to placebo in treating depression in individuals with physical illness, although reporting bias may have exaggerated this finding.
Limitations and strategies
Among individuals treated with a given antidepressant, between 30% and 50% do not show response. Approximately one-third of people achieve a full remission, one-third experience a response, and one-third are nonresponders. Partial remission is characterized by the presence of poorly defined residual symptoms. These symptoms typically include depressed mood, anxiety, sleep disturbance, fatigue, and diminished interest or pleasure. It is currently unclear which factors predict partial remission. However, it is clear that residual symptoms are powerful predictors of relapse, with relapse rates three to six times higher in people with residual symptoms than in those who experience full remission. In addition, antidepressant drugs tend to lose efficacy over the course of treatment. According to data from the Centers for Disease Control and Prevention
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...
, less than one-third of Americans taking one antidepressant medication have seen a mental health professional in the previous year. A number of strategies are used in clinical practice to try to overcome these limits and variations. They include switching medication, augmentation, and combination.
Switching antidepressants
The American Psychiatric Association
The American Psychiatric Association (APA) is the main professional organization of psychiatrists and trainee psychiatrists in the United States, and the largest psychiatric organization in the world. It has more than 37,000 members are involve ...
2000 Practice Guideline advises that where no response is achieved within the following six to eight weeks of treatment with an antidepressant, switch to an antidepressant in the same class, and then to a different class. A 2006 meta-analysis review found wide variation in the findings of prior studies: for people who had failed to respond to an SSRI antidepressant, between 12% and 86% showed a response to a new drug. However, the more antidepressants an individual had previously tried, the less likely they were to benefit from a new antidepressant trial. However, a later meta-analysis found no difference between switching to a new drug and staying on the old medication: although 34% of treatment-resistant people responded when switched to the new drug, 40% responded without being switched.
Augmentation and combination
For a partial response, the American Psychiatric Association (APA) guidelines suggest augmentation, or adding a drug from a different class. These include lithium
Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid el ...
and thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...
augmentation, dopamine agonist
A dopamine agonist (DA) is a compound that activates dopamine receptors. There are two families of dopamine receptors, D2-like and D1-like, and they are all G protein-coupled receptors. D1- and D5-receptors belong to the D1-like family and the ...
s, sex steroid
Sex hormones, also known as sex steroids, gonadocorticoids and gonadal steroids, are steroid hormones that interact with vertebrate steroid hormone receptors. The sex hormones include the androgens, estrogens, and progestogens. Their effects are ...
s, NRIs, glucocorticoid
Glucocorticoids (or, less commonly, glucocorticosteroids) are a class of corticosteroids, which are a class of steroid hormones. Glucocorticoids are corticosteroids that bind to the glucocorticoid receptor that is present in almost every vertebr ...
-specific agents, or the newer anticonvulsant
Anticonvulsants (also known as antiepileptic drugs or recently as antiseizure drugs) are a diverse group of pharmacological agents used in the treatment of epileptic seizures. Anticonvulsants are also increasingly being used in the treatment of b ...
s.
A combination strategy involves adding another antidepressant, usually from a different class so as to have effect on other mechanisms. Although this may be used in clinical practice, there is little evidence for the relative efficacy or adverse effects of this strategy. Other tests conducted include the use of psychostimulants as an augmentation therapy. Several studies have shown the efficacy of combining modafinil
Modafinil, sold under the brand name Provigil among others, is a central nervous system (CNS) stimulant medication used to treat sleepiness due to narcolepsy, shift work sleep disorder, and obstructive sleep apnea. While it has seen off-label ...
for treatment-resistant people. It has been used to help combat SSRI-associated fatigue.
Long-term use and stopping
The effects of antidepressants typically do not continue once the course of medication ends. This results in a high rate of relapse
In internal medicine, relapse or recidivism is a recurrence of a past (typically medical) condition. For example, multiple sclerosis and malaria often exhibit peaks of activity and sometimes very long periods of dormancy, followed by relapse or r ...
. In 2003, a meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...
found that 18% of people who had responded to an antidepressant relapsed while still taking it, compared to 41% whose antidepressant was switched for a placebo
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures.
In general ...
.
A gradual loss of therapeutic benefit occurs in a minority of people during the course of treatment. A strategy involving the use of pharmacotherapy
Pharmacotherapy is therapy using pharmaceutical drugs, as distinguished from therapy using surgery (surgical therapy), radiation (radiation therapy), movement ( physical therapy), or other modes. Among physicians, sometimes the term ''medical the ...
in the treatment of the acute episode, followed by psychotherapy in its residual phase, has been suggested by some studies. For patients who wish to stop their antidepressants
Antidepressants are a class of medication used to treat major depressive disorder, anxiety disorders, chronic pain conditions, and to help manage addictions. Common side-effects of antidepressants include dry mouth, weight gain, dizziness, heada ...
, engaging in brief psychological interventions such as Preventive Cognitive Therapy or Mindfulness-based Cognitive Therapy
Mindfulness-based cognitive therapy (MBCT) is an approach to psychotherapy that uses cognitive behavioral therapy (CBT) methods in collaboration with mindfulness meditative practices and similar psychological strategies. The origins to its concept ...
while tapering down has been found to diminish the risk for relapse
In internal medicine, relapse or recidivism is a recurrence of a past (typically medical) condition. For example, multiple sclerosis and malaria often exhibit peaks of activity and sometimes very long periods of dormancy, followed by relapse or r ...
.
Adverse effects
Antidepressants can cause various adverse effects
An adverse effect is an undesired harmful effect resulting from a medication or other intervention, such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. The term complica ...
, depending on the individual and the drug in question.
Almost any medication involved with serotonin regulation has the potential to cause serotonin toxicity (also known as ''serotonin syndrome'') — an excess of serotonin that can induce mania, restlessness, agitation, emotional lability
In medicine and psychology, emotional lability is a sign or symptom typified by exaggerated changes in mood or affect in quick succession. Sometimes the emotions expressed outwardly are very different from how the person feels on the inside. Thes ...
, insomnia and confusion as its primary symptoms. Although the condition is serious, it is not particularly common, generally only appearing at high doses or while on other medications. Assuming proper medical intervention has been taken (within about 24 hours) it is rarely fatal. Antidepressants appear to increase the risk of diabetes
Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ap ...
by about 1.3 fold.
MAOIs
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especi ...
tend to have pronounced (sometimes fatal) interactions with a wide variety of medications and over-the-counter drug
Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs
A prescription drug (also prescription medication or prescripti ...
s. If taken with foods that contain very high levels of tyramine
Tyramine ( ) (also spelled tyramin), also known under several other names, is a naturally occurring trace amine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent. Notably, it is unable to cross the blood-b ...
(e.g., mature cheese, cured meats, or yeast extracts), they may cause a potentially lethal hypertensive crisis
Severely elevated blood pressure (equal to or greater than a systolic 180 or diastolic of 120—sometimes termed malignant or accelerated hypertension) is referred to as a hypertensive crisis, as blood pressure at this level confers a high risk ...
. At lower doses, the person may only experience a headache due to an increase in blood pressure.
In response to these adverse effects, a different type of MAOI has been developed: the reversible inhibitor of monoamine oxidase A
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, especia ...
(RIMA) class of drugs. Their primary advantage is that they do not require the person to follow a special diet, while being purportedly effective as SSRIs and tricyclics in treating depressive disorders.
Tricyclics and SSRI can cause the so-called drug-induced QT prolongation QT prolongation is a measure of delayed ventricular repolarisation, which means the heart muscle takes longer than normal to recharge between beats. It is an electrical disturbance which can be seen on an electrocardiogram (ECG). Excessive QT prolo ...
, especially in older adults; this condition can degenerate into a specific type of abnormal heart rhythm
Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults ...
called torsades de points which can potentially lead to sudden cardiac arrest
Cardiac arrest is when the heart suddenly and unexpectedly stops beating. It is a medical emergency that, without immediate medical intervention, will result in sudden cardiac death within minutes. Cardiopulmonary resuscitation (CPR) and possib ...
.
Some antidepressants are also believed to increase thoughts of suicidal ideation
Suicidal ideation, or suicidal thoughts, means having thoughts, ideas, or ruminations about the possibility of ending one's own life.World Health Organization, ''ICD-11 for Mortality and Morbidity Statistics'', ver. 09/2020MB26.A Suicidal ideatio ...
.
Pregnancy
SSRI use in pregnancy has been associated with a variety of risks with varying degrees of proof of causation. As depression is independently associated with negative pregnancy outcomes, determining the extent to which observed associations between antidepressant use and specific adverse outcomes reflects a causative relationship has been difficult in some cases. In other cases, the attribution of adverse outcomes to antidepressant exposure seems fairly clear.
SSRI use in pregnancy is associated with an increased risk of spontaneous abortion of about 1.7-fold, and is associated with preterm birth and low birth weight.
A systematic review of the risk of major birth defects in antidepressant-exposed pregnancies found a small increase (3% to 24%) in the risk of major malformations and a risk of cardiovascular birth defects that did not differ from non-exposed pregnancies. A study of fluoxetine-exposed pregnancies found a 12% increase in the risk of major malformations that did not reach statistical significance. Other studies have found an increased risk of cardiovascular birth defects among depressed mothers not undergoing SSRI treatment, suggesting the possibility of ascertainment bias, e.g. that worried mothers may pursue more aggressive testing of their infants. Another study found no increase in cardiovascular birth defects and a 27% increased risk of major malformations in SSRI exposed pregnancies.[ The FDA advises for the risk of birth defects with the use of paroxetine and the MAOI should be avoided.
A 2013 systematic review and meta-analysis found that antidepressant use during pregnancy was statistically significantly associated with some pregnancy outcomes, such as gestational age and preterm birth, but not with other outcomes. The same review cautioned that because differences between the exposed and unexposed groups were small, it was doubtful whether they were clinically significant.
A ]neonate
An infant or baby is the very young offspring of human beings. ''Infant'' (from the Latin word ''infans'', meaning 'unable to speak' or 'speechless') is a formal or specialised synonym for the common term ''baby''. The terms may also be used to ...
(infant less than 28 days old) may experience a withdrawal syndrome
Drug withdrawal, drug withdrawal syndrome, or substance withdrawal syndrome, is the group of symptoms that occur upon the abrupt discontinuation or decrease in the intake of pharmaceutical or recreational drugs.
In order for the symptoms of wit ...
from abrupt discontinuation of the antidepressant at birth. Antidepressants have been shown to be present in varying amounts in breast milk, but their effects on infants are currently unknown.
Moreover, SSRIs inhibit nitric oxide synthesis, which plays an important role in setting vascular tone. Several studies have pointed to an increased risk of prematurity associated with SSRI use, and this association may be due to an increase risk of pre-eclampsia
Pre-eclampsia is a disorder of pregnancy characterized by the onset of high blood pressure and often a significant amount of protein in the urine. When it arises, the condition begins after 20 weeks of pregnancy. In severe cases of the disease ...
of pregnancy.
Antidepressant-induced mania
Another possible problem with antidepressants is the chance of antidepressant-induced mania
Mania, also known as manic syndrome, is a mental and behavioral disorder defined as a state of abnormally elevated arousal, affect, and energy level, or "a state of heightened overall activation with enhanced affective expression together wit ...
or hypomania
Hypomania (literally "under mania" or "less than mania") is a mental and behavioural disorder, characterised essentially by an apparently non-contextual elevation of mood ( euphoria) that contributes to persistently disinhibited behaviour.
Th ...
in people with or without a diagnosis of bipolar disorder
Bipolar disorder, previously known as manic depression, is a mental disorder characterized by periods of depression and periods of abnormally elevated mood that last from days to weeks each. If the elevated mood is severe or associated with ...
. Many cases of bipolar depression are very similar to those of unipolar depression. Therefore, the person can be misdiagnosed with unipolar depression and be given antidepressants. Studies have shown that antidepressant-induced mania can occur in 20–40% of people with bipolar disorder. For bipolar depression, antidepressants (most frequently SSRIs) can exacerbate or trigger symptoms of hypomania
Hypomania (literally "under mania" or "less than mania") is a mental and behavioural disorder, characterised essentially by an apparently non-contextual elevation of mood ( euphoria) that contributes to persistently disinhibited behaviour.
Th ...
and mania
Mania, also known as manic syndrome, is a mental and behavioral disorder defined as a state of abnormally elevated arousal, affect, and energy level, or "a state of heightened overall activation with enhanced affective expression together wit ...
.
Suicide
Studies have shown that the use of antidepressants is correlated with an increased risk of suicidal behavior and thinking (suicidality) in those aged under 25 years old. This problem has been serious enough to warrant government intervention by the US Food and Drug Administration (FDA) to warn of the increased risk of suicidality during antidepressant treatment. According to the FDA, the heightened risk of suicidality occurs within the first one to two months of treatment. The National Institute for Health and Care Excellence (NICE) places the excess risk in the "early stages of treatment". A meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...
suggests that the relationship between antidepressant use and suicidal behavior or thoughts is age-dependent. Compared with placebo, the use of antidepressants is associated with an increase in suicidal behavior or thoughts among those 25 years old or younger ( OR=1.62). A review of RCTs and epidemiological studies by Healy and Whitaker found an increase of suicidal acts by a factor of 2.4. There is no effect or possibly a mild protective effect among those aged 25 to 64 (OR=0.79). Antidepressant treatment has a protective effect against suicidality among those aged 65 and over (OR=0.37).
Sexual dysfunction
Sexual side effects are also common with SSRIs, such as loss of sexual drive
Libido (; colloquial: sex drive) is a person's overall sexual drive or desire for sexual activity. Libido is influenced by biological, psychological, and social factors. Biologically, the sex hormones and associated neurotransmitters that act up ...
, failure to reach orgasm, and erectile dysfunction
Erectile dysfunction (ED), also called impotence, is the type of sexual dysfunction in which the penis fails to become or stay erect during sexual activity. It is the most common sexual problem in men.Cunningham GR, Rosen RC. Overview of male ...
. Although usually reversible, these sexual side-effects can, in rare cases, continue after the drug has been completely withdrawn.
In a study of 1,022 outpatients, overall sexual dysfunction with all antidepressants averaged 59.1% with SSRI values between 57% and 73%, Mirtazapine 24%, Nefazodone 8%, Amineptine 7% and Moclobemide 4%. Moclobemide
Moclobemide, sold under the brand names Amira, Aurorix, Clobemix, Depnil and Manerix among others, is a reversible inhibitor of monoamine oxidase A (RIMA) drug primarily used to treat depression and social anxiety. It is not approved for use in t ...
, a selective reversible MAO-A inhibitor, does not cause sexual dysfunction, and can actually lead to an improvement in all aspects of sexual function.
Biochemical mechanisms suggested as causative include increased serotonin, particularly affecting 5-HT2 and 5-HT3 receptors; decreased dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...
; decreased norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
; blockade of cholinergic
Cholinergic agents are compounds which mimic the action of acetylcholine and/or butyrylcholine. In general, the word "choline" describes the various quaternary ammonium salts containing the ''N'',''N'',''N''-trimethylethanolammonium cation. F ...
and α1adrenergic receptors; inhibition of nitric oxide synthetase; and elevation of prolactin
Prolactin (PRL), also known as lactotropin, is a protein best known for its role in enabling mammals to produce milk. It is influential in over 300 separate processes in various vertebrates, including humans. Prolactin is secreted from the pit ...
levels. Mirtazapine
Mirtazapine, sold under the brand name Remeron amongst others, is an atypical antidepressant, and as such is used primarily to treat depression. Its effects may take up to four weeks, but can also manifest as early as one to two weeks. It is o ...
is reported to have fewer sexual side effects, most likely because it antagonizes 5-HT2 and 5-HT3 receptors and may, in some cases, reverse sexual dysfunction induced by SSRIs by the same mechanism.
Bupropion
Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the case ...
, a weak NDRI and nicotinic antagonist, may be useful in treating reduced libido as a result of SSRI
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracellul ...
treatment.
Emotional blunting
Certain antidepressants may cause emotional blunting
Reduced affect display, sometimes referred to as emotional blunting or emotional numbing, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings ( affect display) either verbally or nonverba ...
, characterized by reduced intensity of both positive and negative emotions as well as symptoms of apathy
Apathy is a lack of feeling, emotion, interest, or concern about something. It is a state of indifference, or the suppression of emotions such as concern, excitement, motivation, or passion. An apathetic individual has an absence of intere ...
, indifference, and amotivation. It may be experienced as either beneficial or detrimental depending on the situation. This side effect has been particularly associated with serotonergic antidepressants like SSRIs and SNRIs, but may be less with atypical antidepressants like Bupropion
Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the case ...
, Agomelatine
Agomelatine, sold under the brand names Valdoxan and Thymanax, among others, is an atypical antidepressant most commonly used to treat major depressive disorder and generalized anxiety disorder. One review found that it is as effective as other a ...
, and Vortioxetine
Vortioxetine, sold under the brand names Trintellix and Brintellix among others, is a medication used to treat major depressive disorder. Effectiveness is viewed as similar to that of other antidepressants. It is taken by mouth.
Common side e ...
. Higher doses of antidepressants seem to be more likely to produce emotional blunting than lower doses. It can be decreased by reducing dosage, discontinuing the medication, or switching to a different antidepressant that may have less propensity for causing this side effect.
Changes in weight
Changes in appetite or weight are common among antidepressants, but are largely drug-dependent and related to which neurotransmitters they affect. Mirtazapine
Mirtazapine, sold under the brand name Remeron amongst others, is an atypical antidepressant, and as such is used primarily to treat depression. Its effects may take up to four weeks, but can also manifest as early as one to two weeks. It is o ...
and paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
, for example, may be associated with weight gain and/or increased appetite, while others (such as bupropion
Bupropion, sold under the brand names Wellbutrin and Zyban among others, is an atypical antidepressant primarily used to treat major depressive disorder and to support smoking cessation. It is also popular as an add-on medication in the case ...
and venlafaxine
Venlafaxine, sold under the brand name Effexor among others, is an antidepressant medication of the serotonin-norepinephrine reuptake inhibitor (SNRI) class. It is used to treat major depressive disorder, generalized anxiety disorder, panic di ...
) achieve the opposite effect.
The antihistaminic properties of certain TCA- and TeCA-class antidepressants have been shown to contribute to the common side effects of increased appetite and weight gain associated with these classes of medication.
Risk of death
A 2017 meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...
found that antidepressants were associated with significantly increased risk of death (+33%) and new cardiovascular complications (+14%) in the general population. Conversely, risks were not greater in people with existing cardiovascular disease
Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, h ...
.
Discontinuation syndrome
Antidepressant discontinuation syndrome, also called antidepressant withdrawal syndrome, is a condition that can occur following the interruption, reduction, or discontinuation of antidepressant medication.[ The symptoms may include ]flu-like symptoms
Influenza-like illness (ILI), also known as flu-like syndrome or flu-like symptoms, is a medical diagnosis of possible influenza or other illness causing a set of common symptoms. These include fever, shivering, chills, malaise, dry cough, loss ...
, trouble sleeping, nausea, poor balance, sensory changes, and anxiety
Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...
. The problem usually begins within three days and may last for several months.[ Rarely ]psychosis
Psychosis is a condition of the mind that results in difficulties determining what is real and what is not real. Symptoms may include delusions and hallucinations, among other features. Additional symptoms are incoherent speech and behavior ...
may occur.[
A discontinuation syndrome can occur after stopping any antidepressant including ]selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracell ...
s (SSRIs), serotonin–norepinephrine reuptake inhibitor
Serotonin–norepinephrine reuptake inhibitors (SNRIs) are a class of antidepressant drugs used to treat major depressive disorder (MDD), anxiety disorders, obsessive–compulsive disorder (OCD), social phobia, attention-deficit hyperactivity dis ...
s (SNRIs), and tricyclic antidepressants
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...
(TCAs).[ The risk is greater among those who have taken the medication for longer and when the medication in question has a short ]half-life
Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable ato ...
.[ The underlying reason for its occurrence is unclear.][ The diagnosis is based on the symptoms.][
Methods of prevention include gradually decreasing the dose among those who wish to stop, though it is possible for symptoms to occur with tapering.] Treatment may include restarting the medication and slowly decreasing the dose.[ People may also be switched to the long acting antidepressant ]fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
which can then be gradually decreased.[
Approximately 20–50% of people who suddenly stop an antidepressant develop an antidepressant discontinuation syndrome.] The condition is generally not serious.[ Though about half of people with symptoms describe them as severe.][ Some restart antidepressants due to the severity of the symptoms.][
]
Pharmacology
Antidepressants act via a large number of different mechanisms of action
In pharmacology, the term mechanism of action (MOA) refers to the specific biochemical interaction through which a drug substance produces its pharmacological effect. A mechanism of action usually includes mention of the specific molecular targe ...
. This includes serotonin reuptake inhibition (SSRIs, SNRIs, TCAs, Vilazodone, Vortioxetine), Norepinephrine reuptake inhibition (NRIs, SNRIs, TCAs), dopamine reuptake inhibition (Bupropion, Amineptine, Nomifensine), direct modulation
In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the ''carrier signal'', with a separate signal called the ''modulation signal'' that typically contains informatio ...
of Monoamine receptors (Vilazodone, Vortioxetine, SARIs, Agomelatine, TCAs, TeCAs, Antipsychotics), Monoamine oxidase inhibition (MAOIs), and NMDA receptor antagonism
NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the ''N''-Methyl-D-aspartate receptor ( NMDAR). They are commonly used as anesthetics for animals and humans; the state of anesthesia they induce ...
(Ketamine, Esketamine, Dextromethorphan), among others (e.g., Brexanolone, Tianeptine). Some antidepressants also have additional actions, like sigma receptor
Sigma receptors (σ-receptors) are protein cell surface receptors that bind ligands such as 4-PPBP (4-phenyl-1-(4-phenylbutyl) piperidine), SA 4503 (cutamesine), ditolylguanidine, dimethyltryptamine, and siramesine. There are two subtypes, ...
modulation (certain SSRIs, TCAs, dextromethorphan) and antagonism of histamine
Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered in ...
H1 and muscarinic acetylcholine receptor
Muscarinic acetylcholine receptors, or mAChRs, are acetylcholine receptors that form G protein-coupled receptor complexes in the cell membranes of certain neurons and other cells. They play several roles, including acting as the main end-rece ...
s (TCAs, TeCAs).
The earliest and most widely known scientific theory
A scientific theory is an explanation of an aspect of the natural world and universe that has been repeatedly tested and corroborated in accordance with the scientific method, using accepted protocols of observation, measurement, and evaluatio ...
of antidepressant action is the monoamine hypothesis, which can be traced back to the 1950s and 1960s. This theory states that depression is due to an imbalance, most often a deficiency, of the monoamine neurotransmitter
Monoamine neurotransmitters are neurotransmitters and neuromodulators that contain one amino group connected to an aromaticity, aromatic ring by a two-carbon chain (such as -CH2-CH2-). Examples are dopamine, norepinephrine and serotonin.
All mo ...
s, namely serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
, norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
, and/or dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...
. However, serotonin in particular has been implicated, as in the serotonin hypothesis of depression. The monoamine hypothesis was originally proposed based on observations that Reserpine
Reserpine is a drug that is used for the treatment of high blood pressure, usually in combination with a thiazide diuretic or vasodilator. Large clinical trials have shown that combined treatment with reserpine plus a thiazide diuretic reduces m ...
, a drug which depletes the monoamine neurotransmitters, produced depressive effects in people, and that certain Hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly toxic unless handled in solution as, for example, hydrazine ...
antituberculosis agents like Iproniazid
Iproniazid (Marsilid, Rivivol, Euphozid, Iprazid, Ipronid, Ipronin) is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class. It is a xenobiotic that was originally designed to treat tuberculosis, but was lat ...
, which prevent the breakdown of monoamine neurotransmitters, produced apparent antidepressant effects. Most currently marketed antidepressants, which are monoaminergic
Monoaminergic means "working on monoamine neurotransmitters", which include serotonin, dopamine, norepinephrine, epinephrine, and histamine.
A monoaminergic, or monoaminergic drug, is a chemical, which functions to directly modulate the ser ...
in their actions, are theoretically consistent with the monoamine hypothesis. Despite the widespread nature of the monoamine hypothesis, it has a number of limitations: for one, all monoaminergic antidepressants have a delayed onset of action of at least a week; and secondly, many people with depression do not respond to monoaminergic antidepressants. A number of alternative hypotheses have been proposed, including hypotheses involving Glutamate
Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can syn ...
, Neurogenesis
Neurogenesis is the process by which nervous system cells, the neurons, are produced by neural stem cells (NSCs). It occurs in all species of animals except the porifera (sponges) and placozoans. Types of NSCs include neuroepithelial cells (NECs) ...
, Epigenetics
In biology, epigenetics is the study of stable phenotypic changes (known as ''marks'') that do not involve alterations in the DNA sequence. The Greek prefix '' epi-'' ( "over, outside of, around") in ''epigenetics'' implies features that are "o ...
, Cortisol
Cortisol is a steroid hormone, in the glucocorticoid class of hormones. When used as a medication, it is known as hydrocortisone.
It is produced in many animals, mainly by the ''zona fasciculata'' of the adrenal cortex in the adrenal gland ...
Hypersecretion 440px
Secretion is the movement of material from one point to another, such as a secreted chemical substance from a cell or gland. In contrast, excretion is the removal of certain substances or waste products from a cell or organism. The classical ...
, and Inflammation
Inflammation (from la, wikt:en:inflammatio#Latin, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or Irritation, irritants, and is a protective response involving im ...
, among others.
In 2022, a major systematic umbrella review by Joanna Moncrieff
Joanna Moncrieff is a British psychiatrist and academic. She is Professor of Critical and Social Psychiatry at University College London and a leading figure in the Critical Psychiatry Network. She is a prominent critic of the modern ' psychopha ...
and colleagues showed that the serotonin theory of depression was not supported by the evidence from a wide variety of areas. The authors concluded that there is no association between serotonin and depression, and that there is no evidence that strongly supports the theory that depression is caused by low serotonin activity or concentrations. Other literature had described the lack of support for the theory previously. In many of the expert responses to the review, it was stated that the monoamine hypothesis had long already been abandoned by psychiatry. This is in spite of about 90% of the general public in Western countries believing the theory to be true and many in the field of psychiatry continuing to promote the theory up to recent times. In addition to this review, a 2003 literature review
A literature review is an overview of the previously published works on a topic. The term can refer to a full scholarly paper or a section of a scholarly work such as a book, or an article. Either way, a literature review is supposed to provid ...
and a 2022 systematic review, both of reserpine and mood, found that in fact there is no consistent evidence that reserpine produces depressive effects. Instead, the results were highly mixed, with similar proportions of studies finding that reserpine had no influence on mood, produced depressogenic effects, or had antidepressant effects. In relation to this, the general monoamine hypothesis, as opposed to just the serotonin theory of depression, is likewise not well-supported by evidence.
The serotonin and monoamine hypotheses of depression have been heavily promoted by the pharmaceutical industry
The pharmaceutical industry discovers, develops, produces, and markets drugs or pharmaceutical drugs for use as medications to be administered to patients (or self-administered), with the aim to cure them, vaccinate them, or alleviate symptoms. ...
(e.g., in advertisement
Advertising is the practice and techniques employed to bring attention to a product or service. Advertising aims to put a product or service in the spotlight in hopes of drawing it attention from consumers. It is typically used to promote a ...
s) and by the psychiatric profession at large despite the lack of evidence in support of them. In the case of the pharmaceutical industry, this can be attributed to obvious financial incentives, with the theory creating bias against non-pharmacological treatment
A non-pharmaceutical intervention or non-pharmacological intervention (NPI) is any type of health intervention which is not primarily based on medication. Some examples include exercise, sleep improvement, or dietary habits.
Non-pharmacological ...
s for depression.
An alternative theory for antidepressant action proposed by certain academics such as Irving Kirsch is that they work largely or entirely via placebo
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures.
In general ...
mechanisms. This is supported by meta-analyses of antidepressant randomized controlled trial
A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical te ...
s, which consistently show that placebo groups in trials improve about 80 to 90% as much as antidepressant groups on average and that antidepressants are only marginally more effective for depression than placebos. The difference between antidepressants and placebo corresponds to an effect size
In statistics, an effect size is a value measuring the strength of the relationship between two variables in a population, or a sample-based estimate of that quantity. It can refer to the value of a statistic calculated from a sample of data, the ...
( SMD) of about 0.3, which in turn equates to about a 2- to 3-point additional improvement on the 0–52-point ( HRSD) and 0–60-point ( MADRS) depression rating scale
A depression rating scale is a psychometric instrument (tool), usually a questionnaire whose wording has been validated with experimental evidence, having descriptive words and phrases that indicate the severity of depression for a time period ...
s used in trials. This small advantage of antidepressants over placebo is often statistically significant
In statistical hypothesis testing, a result has statistical significance when it is very unlikely to have occurred given the null hypothesis (simply by chance alone). More precisely, a study's defined significance level, denoted by \alpha, is the p ...
and is the basis for their regulatory approval, but is sufficiently modest that its clinical significance In medicine and psychology, clinical significance is the practical importance of a treatment effect—whether it has a real genuine, palpable, noticeable effect on daily life.
Types of significance Statistical significance
Statistical significance ...
is doubtful. Moreover, the small advantage of antidepressants over placebo may simply be a methodological artifact
In its most common sense, methodology is the study of research methods. However, the term can also refer to the methods themselves or to the philosophical discussion of associated background assumptions. A method is a structured procedure for bri ...
caused by unblinding
In a blind or blinded experiment, information which may influence the participants of the experiment is withheld until after the experiment is complete. Good blinding can reduce or eliminate experimental biases that arise from a participants' expec ...
due to the psychoactive
A psychoactive drug, psychopharmaceutical, psychoactive agent or psychotropic drug is a chemical substance, that changes functions of the nervous system, and results in alterations in perception, mood, consciousness, cognition or behavior.
Th ...
effects and side effect
In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...
s of antidepressants, in turn resulting in enhanced placebo effects and apparent antidepressant efficacy. Placebos are not purely psychological phenomenon, but have been found to modify the activity of several brain regions and to increase levels of dopamine and endogenous
Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell.
In contrast, exogenous substances and processes are those that originate from outside of an organism.
For example, es ...
opioid
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid us ...
s in the reward pathway
The mesolimbic pathway, sometimes referred to as the reward pathway, is a dopaminergic pathway in the brain. The pathway connects the ventral tegmental area in the midbrain to the ventral striatum of the basal ganglia in the forebrain. The ventra ...
s. It has been argued by Kirsch that although antidepressants may be used efficaciously for depression as active placebo An active placebo is a placebo that produces noticeable side effects that may convince the person being treated that they are receiving a legitimate treatment, rather than an ineffective placebo.
Nomenclature
According to a 1965 paper, the term " ...
s, they are limited by significant pharmacological side effect
In medicine, a side effect is an effect, whether therapeutic or adverse, that is secondary to the one intended; although the term is predominantly employed to describe adverse effects, it can also apply to beneficial, but unintended, consequence ...
s and risks, and therefore non-pharmacological therapies, such as psychotherapy
Psychotherapy (also psychological therapy, talk therapy, or talking therapy) is the use of psychological methods, particularly when based on regular personal interaction, to help a person change behavior, increase happiness, and overcome pro ...
and lifestyle changes, which can have similar efficacy to antidepressants but do not have their adverse effects, ought to be preferred as treatments in people with depression.
The placebo response
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like saline), sham surgery, and other procedures.
In general, placebos can aff ...
, or the improvement in scores in the placebo group in clinical trials, is not only due to the placebo effect
A placebo ( ) is a substance or treatment which is designed to have no therapeutic value. Common placebos include inert tablets (like sugar pills), inert injections (like Saline (medicine), saline), sham surgery, and other procedures.
In general ...
, but is also due to other phenomena such as spontaneous remission
Spontaneous remission, also called spontaneous healing or spontaneous regression, is an unexpected improvement or cure from a disease that usually progresses. These terms are commonly used for unexpected transient or final improvements in cancer. S ...
and regression to the mean
In statistics, regression toward the mean (also called reversion to the mean, and reversion to mediocrity) is the fact that if one sample of a random variable is extreme, the next sampling of the same random variable is likely to be closer to it ...
. Depression tends to have an episodic course, with people eventually recovering even with no medical intervention, and people tend to seek treatment, as well as enroll in clinical trials, when they are feeling their worst. In meta-analyses of trials of depression therapies, Kirsch estimated based on improvement in untreated waiting-list controls that spontaneous remission and regression to the mean only account for about 25% of the improvement in depression scores with antidepressant therapy. However, another academic, Michael P. Hengartner, has argued and presented evidence that spontaneous remission and regression to the mean might actually account for most of the improvement in depression scores with antidepressants, and that the substantial placebo effect observed in clinical trials might largely be a methodological artifact. This suggests that antidepressants may be associated with much less genuine treatment benefit, whether due to the placebo effect or to the antidepressant itself, than has been traditionally assumed.
Types
Selective serotonin reuptake inhibitors
Selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracell ...
s (SSRIs) are believed to increase the extracellular
This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms. It is intended as introductory material for novices; for more specific and technical definitions ...
level of the neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell.
Neuro ...
serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
by limiting
In electronics, a limiter is a circuit that allows signals below a specified input power or level to pass unaffected while attenuating (lowering) the peaks of stronger signals that exceed this threshold. Limiting is a type of dynamic range comp ...
its reabsorption
In renal physiology, reabsorption or tubular reabsorption is the process by which the nephron removes water and solutes from the tubular fluid (pre-urine) and returns them to the circulating blood. It is called ''reabsorption'' (and not ''absorpt ...
into the presynaptic cell
Chemical synapses are biological junctions through which neurons' signals can be sent to each other and to non-neuronal cells such as those in neuromuscular junction, muscles or glands. Chemical synapses allow neurons to form biological neural ...
, increasing the level of serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
in the synaptic cleft
Chemical synapses are biological junctions through which neurons' signals can be sent to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous syste ...
available to bind to the postsynaptic receptor. They have varying degrees of selectivity for the other monoamine transporter
Monoamine transporters (MATs) are protein structures that function as integral plasma-membrane transporters to regulate concentrations of extracellular monoamine neurotransmitters. Three major classes of MATs (SERT, DAT, NET) are responsible for ...
s, with pure SSRIs having only weak affinity for the norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
and dopamine transporter
The dopamine transporter (also dopamine active transporter, DAT, SLC6A3) is a membrane-spanning protein that pumps the neurotransmitter dopamine out of the synaptic cleft back into cytosol. In the cytosol, other transporters sequester the dopam ...
s.
SSRIs are the most widely prescribed antidepressants in many countries. The efficacy of SSRIs in mild or moderate cases of depression has been disputed.
Serotonin–norepinephrine reuptake inhibitors
Serotonin–norepinephrine reuptake inhibitor
Serotonin–norepinephrine reuptake inhibitors (SNRIs) are a class of antidepressant drugs used to treat major depressive disorder (MDD), anxiety disorders, obsessive–compulsive disorder (OCD), social phobia, attention-deficit hyperactivity dis ...
s (SNRIs) are potent inhibitors of the reuptake
Reuptake is the reabsorption of a neurotransmitter by a neurotransmitter transporter located along the plasma membrane of an axon terminal (i.e., the pre-synaptic neuron at a synapse) or glial cell after it has performed its function of transm ...
of serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
and norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
. These neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell.
Neuro ...
s are known to play an important role in mood. SNRIs can be contrasted with the more widely used selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracell ...
s (SSRIs), which act mostly upon serotonin alone.
The human serotonin transporter
The serotonin transporter (SERT or 5-HTT) also known as the sodium-dependent serotonin transporter and solute carrier family 6 member 4 is a protein that in humans is encoded by the SLC6A4 gene. SERT is a type of monoamine transporter protein tha ...
(SERT) and norepinephrine transporter
The norepinephrine transporter (NET), also known as noradrenaline transporter (NAT), is a protein that in humans is encoded by the solute carrier family 6 member 2 (SLC6A2) gene.
NET is a monoamine transporter and is responsible for the sodium- ...
(NET) are membrane protein
Membrane proteins are common proteins that are part of, or interact with, biological membranes. Membrane proteins fall into several broad categories depending on their location. Integral membrane proteins are a permanent part of a cell membrane ...
s that are responsible for the reuptake of serotonin and norepinephrine. Balanced dual inhibition of monoamine
Monoamine neurotransmitters are neurotransmitters and neuromodulators that contain one amino group connected to an aromatic ring by a two-carbon chain (such as -CH2-CH2-). Examples are dopamine, norepinephrine and serotonin.
All monoamines are ...
reuptake can possibly offer advantages over other antidepressants drugs by treating a wider range of symptoms.
SNRIs are sometimes also used to treat anxiety disorder
Anxiety disorders are a cluster of mental disorders characterized by significant and uncontrollable feelings of anxiety and fear such that a person's social, occupational, and personal function are significantly impaired. Anxiety may cause physi ...
s, obsessive–compulsive disorder
Obsessive–compulsive disorder (OCD) is a mental and behavioral disorder in which an individual has intrusive thoughts and/or feels the need to perform certain routines repeatedly to the extent where it induces distress or impairs general ...
(OCD), attention deficit hyperactivity disorder
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterised by excessive amounts of inattention, hyperactivity, and impulsivity that are pervasive, impairing in multiple contexts, and otherwise age-inap ...
(ADHD), chronic neuropathic pain
Neuropathic pain is pain caused by damage or disease affecting the somatosensory system. Neuropathic pain may be associated with abnormal sensations called dysesthesia or pain from normally non-painful stimuli (allodynia). It may have continuous ...
, and fibromyalgia syndrome (FMS), and for the relief of menopausal
Menopause, also known as the climacteric, is the time in women's lives when Menstruation, menstrual periods stop permanently, and they are no longer fertility, able to bear children. Menopause usually occurs between the age of 47 and 54. Medic ...
symptoms.
Serotonin modulators and stimulators
Serotonin modulator and stimulator A serotonin modulator and stimulator (SMS), sometimes referred to more simply as a serotonin modulator, is a type of drug with a multimodal action specific to the serotonin neurotransmitter system. To be precise, SMSs simultaneously modulate one or ...
s (SMSs), sometimes referred to more simply as "serotonin modulators", are a type of drug
A drug is any chemical substance that causes a change in an organism's physiology or psychology when consumed. Drugs are typically distinguished from food and substances that provide nutritional support. Consumption of drugs can be via insuffla ...
with a multimodal action specific to the serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell.
Neuro ...
system. To be precise, SMSs simultaneously modulate one or more serotonin receptor
5-HT receptors, 5-hydroxytryptamine receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems. They mediate both excitatory and inhibitory neur ...
s and inhibit the reuptake
Reuptake is the reabsorption of a neurotransmitter by a neurotransmitter transporter located along the plasma membrane of an axon terminal (i.e., the pre-synaptic neuron at a synapse) or glial cell after it has performed its function of transm ...
of serotonin. The term was coined in reference to the mechanism of action
In pharmacology, the term mechanism of action (MOA) refers to the specific biochemical interaction through which a drug substance produces its pharmacological effect. A mechanism of action usually includes mention of the specific molecular targe ...
of the serotonergic antidepressant Vortioxetine
Vortioxetine, sold under the brand names Trintellix and Brintellix among others, is a medication used to treat major depressive disorder. Effectiveness is viewed as similar to that of other antidepressants. It is taken by mouth.
Common side e ...
, which acts as a serotonin reuptake inhibitor
A serotonin reuptake inhibitor (SRI) is a type of drug which acts as a reuptake inhibitor of the neurotransmitter serotonin (5-hydroxytryptamine, or 5-HT) by blocking the action of the serotonin transporter (SERT). This in turn leads to increase ...
(SRI), partial agonist
In pharmacology, partial agonists are drugs that bind to and activate a given receptor, but have only partial efficacy at the receptor relative to a full agonist. They may also be considered ligands which display both agonistic and antagonistic e ...
of the 5-HT1A receptor, and antagonist
An antagonist is a character in a story who is presented as the chief foe of the protagonist.
Etymology
The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...
of the 5-HT3 and 5-HT7 receptors. However, it can also technically be applied to Vilazodone
Vilazodone, sold under the brand name Viibryd among others, is a medication used to treat major depressive disorder. It is taken by mouth.
Common side effects include nausea, diarrhea, and trouble sleeping. Serious side effects may include in ...
, which is an antidepressant as well and acts as an SRI and 5-HT1A receptor partial agonist.
An alternative term is serotonin partial agonist/reuptake inhibitor (SPARI), which can be applied only to Vilazodone.
Serotonin antagonists and reuptake inhibitors
Serotonin antagonist and reuptake inhibitors (SARIs) while mainly used as antidepressants, are also anxiolytic
An anxiolytic (; also antipanic or antianxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxi ...
s and hypnotic
Hypnotic (from Greek ''Hypnos'', sleep), or soporific drugs, commonly known as sleeping pills, are a class of (and umbrella term for) psychoactive drugs whose primary function is to induce sleep (or surgical anesthesiaWhen used in anesthesia ...
s. They act by antagonizing serotonin receptor
5-HT receptors, 5-hydroxytryptamine receptors, or serotonin receptors, are a group of G protein-coupled receptor and ligand-gated ion channels found in the central and peripheral nervous systems. They mediate both excitatory and inhibitory neur ...
s such as 5-HT2A and inhibiting the reuptake
Reuptake is the reabsorption of a neurotransmitter by a neurotransmitter transporter located along the plasma membrane of an axon terminal (i.e., the pre-synaptic neuron at a synapse) or glial cell after it has performed its function of transm ...
of serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
, norepinephrine
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as both a hormone and neurotransmitter. The name "noradrenaline" (from Latin '' ad'', ...
, and/or dopamine
Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic compound, organic chemical of the catecholamine and phenethylamine families. Dopamine const ...
. Additionally, most also act as α1-adrenergic receptor antagonists
An antagonist is a character in a story who is presented as the chief foe of the protagonist.
Etymology
The English word antagonist comes from the Greek ἀνταγωνιστής – ''antagonistēs'', "opponent, competitor, villain, enemy, riv ...
. The majority of the currently marketed SARIs belong to the phenylpiperazine
1-Phenylpiperazine is a simple chemical compound featuring a phenyl group bound to a piperazine ring. The suffix ‘-piprazole’ is sometimes used in the names of drugs to indicate they belong to this class.
List phenylpiperazine derivativesAlp ...
class of compounds. They include Trazodone
Trazodone, sold under many brand names, is an antidepressant medication. It is used to treat major depressive disorder, anxiety disorders, and difficulties with sleep. The medication is taken orally.
Common side-effects include dry mouth, fe ...
and Nefazodone
Nefazodone, sold formerly under the brand names Serzone, Dutonin, and Nefadar among others, is an atypical antidepressant which was first marketed by Bristol-Myers Squibb (BMS) in 1994 but has since largely been discontinued. BMS withdrew it from ...
.
Tricyclic antidepressants
The majority of the tricyclic antidepressant
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...
s (TCAs) act primarily as serotonin–norepinephrine reuptake inhibitor
Serotonin–norepinephrine reuptake inhibitors (SNRIs) are a class of antidepressant drugs used to treat major depressive disorder (MDD), anxiety disorders, obsessive–compulsive disorder (OCD), social phobia, attention-deficit hyperactivity dis ...
s (SNRIs) by blocking the serotonin transporter
The serotonin transporter (SERT or 5-HTT) also known as the sodium-dependent serotonin transporter and solute carrier family 6 member 4 is a protein that in humans is encoded by the SLC6A4 gene. SERT is a type of monoamine transporter protein tha ...
(SERT) and the norepinephrine transporter
The norepinephrine transporter (NET), also known as noradrenaline transporter (NAT), is a protein that in humans is encoded by the solute carrier family 6 member 2 (SLC6A2) gene.
NET is a monoamine transporter and is responsible for the sodium- ...
(NET), respectively, which results in an elevation of the synaptic concentrations of these neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a synapse. The cell receiving the signal, any main body part or target cell, may be another neuron, but could also be a gland or muscle cell.
Neuro ...
s, and therefore an enhancement of neurotransmission
Neurotransmission (Latin: ''transmissio'' "passage, crossing" from ''transmittere'' "send, let through") is the process by which signaling molecules called neurotransmitters are released by the axon terminal of a neuron (the presynaptic neuron), ...
. Notably, with the sole exception of amineptine
Amineptine, formerly sold under the brand name Survector among others, is an atypical antidepressant of the tricyclic antidepressant (TCA) family. It acts as a selective and mixed dopamine reuptake inhibitor and releasing agent, and to a lesser ...
, the TCAs have weak affinity
Affinity may refer to:
Commerce, finance and law
* Affinity (law), kinship by marriage
* Affinity analysis, a market research and business management technique
* Affinity Credit Union, a Saskatchewan-based credit union
* Affinity Equity Par ...
for the dopamine transporter
The dopamine transporter (also dopamine active transporter, DAT, SLC6A3) is a membrane-spanning protein that pumps the neurotransmitter dopamine out of the synaptic cleft back into cytosol. In the cytosol, other transporters sequester the dopam ...
(DAT), and therefore have low efficacy as dopamine reuptake inhibitor
A dopamine reuptake inhibitor (DRI) is a class of drug which acts as a reuptake inhibitor of the monoamine neurotransmitter dopamine by blocking the action of the dopamine transporter (DAT). Reuptake inhibition is achieved when extracellular dopa ...
s (DRIs).
Although TCAs are sometimes prescribed for depressive disorders, they have been largely replaced in clinical use in most parts of the world by newer antidepressants such as selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracell ...
s (SSRIs), serotonin–norepinephrine reuptake inhibitor
Serotonin–norepinephrine reuptake inhibitors (SNRIs) are a class of antidepressant drugs used to treat major depressive disorder (MDD), anxiety disorders, obsessive–compulsive disorder (OCD), social phobia, attention-deficit hyperactivity dis ...
s (SNRIs) and norepinephrine reuptake inhibitor
A norepinephrine reuptake inhibitor (NRI, NERI) or noradrenaline reuptake inhibitor or adrenergic reuptake inhibitor (ARI), is a type of drug that acts as a reuptake inhibitor for the neurotransmitters norepinephrine (noradrenaline) and epineph ...
s (NRIs). Adverse effects have been found to be of a similar level between TCAs and SSRIs.
Tetracyclic antidepressants
Tetracyclic antidepressants
Tetracyclic antidepressants (TeCAs) are a class of antidepressants that were first introduced in the 1970s. They are named after their tetracyclic chemical structure, containing four rings of atoms, and are closely related to the tricyclic a ...
(TeCAs) are a class of antidepressants that were first introduced in the 1970s. They are named after their chemical structure
A chemical structure determination includes a chemist's specifying the molecular geometry and, when feasible and necessary, the electronic structure of the target molecule or other solid. Molecular geometry refers to the spatial arrangement of at ...
, which contains four rings of atoms, and are closely related to the tricyclic antidepressant
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...
s (TCAs), which contain three rings of atoms.
Monoamine oxidase inhibitors
Monoamine oxidase inhibitor
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, espe ...
s (MAOIs) are chemicals which inhibit the activity of the monoamine oxidase enzyme family. They have a long history of use as medications prescribed for the treatment of depression. They are particularly effective in treating atypical depression
Atypical depression is defined in the ''DSM IV'' as depression that shares many of the typical symptoms of major depressive disorder or dysthymia but is characterized by improved mood in response to positive events. In contrast to those with at ...
. They are also used in the treatment of Parkinson's disease
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...
and several other disorders.
Because of potentially lethal dietary and drug interactions, MAOIs have historically been reserved as a last line of treatment, used only when other classes of antidepressant drugs (for example selective serotonin reuptake inhibitor
Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions.
SSRIs increase the extracell ...
s and tricyclic antidepressant
Tricyclic antidepressants (TCAs) are a class of medications that are used primarily as antidepressants, which is important for the management of depression. They are second-line drugs next to SSRIs. TCAs were discovered in the early 1950s and wer ...
s) have failed.
MAOIs have been found to be effective in the treatment of panic disorder
Panic disorder is a mental disorder, mental and Abnormal behavior, behavioral disease#Disorder, disorder, specifically an anxiety disorder characterized by reoccurring unexpected panic attacks. Panic attacks are sudden periods of intense fear th ...
with agoraphobia
Agoraphobia is a mental and behavioral disorder, specifically an anxiety disorder characterized by symptoms of anxiety in situations where the person perceives their environment to be unsafe with no easy way to escape. These situations can in ...
, social phobia
Social anxiety disorder (SAD), also known as social phobia, is an anxiety disorder characterized by sentiments of fear and anxiety in social situations, causing considerable distress and impaired ability to function in at least some aspects ...
, atypical depression or mixed anxiety and depression, bulimia
Bulimia nervosa, also known as simply bulimia, is an eating disorder characterized by binge eating followed by purging or fasting, and excessive concern with body shape and weight. The aim of this activity is to expel the body of calories eate ...
, and post-traumatic stress disorder
Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on ...
, as well as borderline personality disorder
Borderline personality disorder (BPD), also known as emotionally unstable personality disorder (EUPD), is a personality disorder characterized by a long-term pattern of unstable interpersonal relationships, distorted sense of self, and strong ...
. MAOIs appear to be particularly effective in the management of bipolar depression
Bipolar disorder, previously known as manic depression, is a mental disorder characterized by periods of depression and periods of abnormally elevated mood that last from days to weeks each. If the elevated mood is severe or associated with ...
according to a retrospective-analysis. There are reports of MAOI efficacy in obsessive–compulsive disorder
Obsessive–compulsive disorder (OCD) is a mental and behavioral disorder in which an individual has intrusive thoughts and/or feels the need to perform certain routines repeatedly to the extent where it induces distress or impairs general ...
(OCD), trichotillomania
Trichotillomania (TTM), also known as hair-pulling disorder or compulsive hair pulling, is a mental disorder characterized by a long-term urge that results in the pulling out of one's own hair. A brief positive feeling may occur as hair is remov ...
, dysmorphophobia, and avoidant personality disorder
Avoidant personality disorder (AvPD) is a Cluster C personality disorder characterized by excessive social anxiety and inhibition, fear of intimacy (despite an intense desire for it), severe feelings of inadequacy and inferiority, and an overrelia ...
, but these reports are from uncontrolled case reports.
MAOIs can also be used in the treatment of Parkinson's disease by targeting MAO-B in particular (therefore affecting dopaminergic neuron
Dopaminergic cell groups, DA cell groups, or dopaminergic nuclei are collections of neurons in the central nervous system that synthesize the neurotransmitter dopamine. In the 1960s, dopaminergic neurons or ''dopamine neurons'' were first ident ...
s), as well as providing an alternative for migraine
Migraine (, ) is a common neurological disorder characterized by recurrent headaches. Typically, the associated headache affects one side of the head, is pulsating in nature, may be moderate to severe in intensity, and could last from a few hou ...
prophylaxis
Preventive healthcare, or prophylaxis, consists of measures taken for the purposes of disease prevention.Hugh R. Leavell and E. Gurney Clark as "the science and art of preventing disease, prolonging life, and promoting physical and mental hea ...
. Inhibition of both MAO-A and MAO-B is used in the treatment of clinical depression
Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive low mood, low self-esteem, and loss of interest or pleasure in normally enjoyable activities. Introdu ...
and anxiety disorder
Anxiety disorders are a cluster of mental disorders characterized by significant and uncontrollable feelings of anxiety and fear such that a person's social, occupational, and personal function are significantly impaired. Anxiety may cause physi ...
s.
NMDA receptor antagonists
NMDA receptor antagonist
NMDA receptor antagonists are a class of drugs that work to antagonize, or inhibit the action of, the ''N''-Methyl-D-aspartate receptor (NMDAR). They are commonly used as anesthetics for animals and humans; the state of anesthesia they induce ...
s like Ketamine
Ketamine is a dissociative anesthetic used medically for induction and maintenance of anesthesia. It is also used as a recreational drug. It is one of the safest anesthetics, as, in contrast with opiates, ether, and propofol, it suppresses ne ...
and Esketamine
Esketamine, also known as (S)-ketamine or S(+)-ketamine, is the ''S''(+) enantiomer of ketamine, is a dissociative hallucinogen drug used as a general anesthetic and as an antidepressant for treatment of depression. It is sold under the brand ...
are rapid-acting antidepressants and seem to work via blockade
A blockade is the act of actively preventing a country or region from receiving or sending out food, supplies, weapons, or communications, and sometimes people, by military force.
A blockade differs from an embargo or sanction, which are le ...
of the ionotropic glutamate NMDA receptor
The ''N''-methyl-D-aspartate receptor (also known as the NMDA receptor or NMDAR), is a glutamate receptor and ion channel found in neurons. The NMDA receptor is one of three types of ionotropic glutamate receptors, the other two being AMPA rece ...
.
Others
See the list of antidepressants
This is a complete list of clinically approved prescription antidepressants throughout the world, as well as clinically approved prescription drugs used to augment antidepressants or mood stabilizers, by pharmacological and/or structural classifica ...
and management of depression
Management of depression is the treatment of depression that may involve a number of different therapies: medications, behavior therapy, psychotherapy, and medical devices.
Depression is a symptom of some physical diseases; a side effect of some ...
for other drugs that are not specifically characterized.
Adjuncts
Adjunct medications are an umbrella category of substances that increase the potency or "enhance" antidepressants. They work by affecting variables very close to the antidepressant, sometimes affecting a completely different mechanism of action
In pharmacology, the term mechanism of action (MOA) refers to the specific biochemical interaction through which a drug substance produces its pharmacological effect. A mechanism of action usually includes mention of the specific molecular targe ...
. This may be attempted when depression treatments have not been successful in the past.
Common types of adjunct medication techniques generally fall into the following categories:
* Two or more antidepressants taken together
** From the same class (affecting the same area of the brain, often at a much higher level)
** From different classes (affecting multiple parts of the brain not covered simultaneously by either drug alone)
* An antipsychotic
Antipsychotics, also known as neuroleptics, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but ...
combined with an antidepressant, particularly atypical antipsychotic
The atypical antipsychotics (AAP), also known as second generation antipsychotics (SGAs) and serotonin–dopamine antagonists (SDAs), are a group of antipsychotic drugs (antipsychotic drugs in general are also known as major tranquilizers and ne ...
s such as Aripiprazole
Aripiprazole, sold under the brand names Abilify and Aristada among others, is an atypical antipsychotic. It is primarily used in the treatment of schizophrenia and bipolar disorder. Other uses include as an add-on treatment in major depressiv ...
(Abilify), Quetiapine
Quetiapine, sold under the brand name Seroquel among others, is an atypical antipsychotic medication used for the treatment of schizophrenia, bipolar disorder, and major depressive disorder. Despite being widely used as a sleep aid due to its ...
(Seroquel), Olanzapine
Olanzapine (sold under the trade name Zyprexa among others) is an atypical antipsychotic primarily used to treat schizophrenia and bipolar disorder. For schizophrenia, it can be used for both new-onset disease and long-term maintenance. It is ta ...
(Zyprexa), and Risperidone
Risperidone, sold under the brand name Risperdal among others, is an atypical antipsychotic used to treat schizophrenia and bipolar disorder. It is taken either by mouth or by injection (subcutaneous or intramuscular). The injectable versions ...
(Risperdal).
It is unknown if undergoing psychological therapy
Psychotherapy (also psychological therapy, talk therapy, or talking therapy) is the use of psychological methods, particularly when based on regular personal interaction, to help a person change behavior, increase happiness, and overcome pro ...
at the same time as taking anti-depressants enhances the anti-depressive effect of the medication.
Less common adjuncts
Lithium
Lithium (from el, λίθος, lithos, lit=stone) is a chemical element with the symbol Li and atomic number 3. It is a soft, silvery-white alkali metal. Under standard conditions, it is the least dense metal and the least dense solid el ...
has been used to augment antidepressant therapy in those who have failed to respond to antidepressants alone. Furthermore, Lithium dramatically decreases the suicide risk in recurrent depression. There is some evidence for the addition of a thyroid hormone, triiodothyronine
Triiodothyronine, also known as T3, is a thyroid hormone. It affects almost every physiological process in the body, including growth and development, metabolism, body temperature, and heart rate.
Production of T3 and its prohormone thyroxine ( ...
, in patients with normal thyroid function.
Psychopharmacologists have also tried adding a stimulant
Stimulants (also often referred to as psychostimulants or colloquially as uppers) is an overarching term that covers many drugs including those that increase activity of the central nervous system and the body, drugs that are pleasurable and inv ...
, in particular, D-amphetamine. However, the use of stimulants in cases of treatment-resistant depression is relatively controversial. A review article published in 2007 found psychostimulants may be effective in treatment-resistant depression with concomitant antidepressant therapy, but a more certain conclusion could not be drawn due to substantial deficiencies in the studies available for consideration, and the somewhat contradictory nature of their results.
History
Before the 1950s, opioid
Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid us ...
s and amphetamine
Amphetamine (contracted from alpha- methylphenethylamine) is a strong central nervous system (CNS) stimulant that is used in the treatment of attention deficit hyperactivity disorder (ADHD), narcolepsy, and obesity. It is also commonly used ...
s were commonly used as antidepressants. Their use was later restricted due to their addictive nature and side effects. Extracts from the herb St John's wort
''Hypericum perforatum'', known as St. John's wort, is a flowering plant in the family Hypericaceae and the type species of the genus ''Hypericum''.
Possibly a hybrid between '' H. maculatum'' and '' H. attenuatum'', the species can be found a ...
have been used as a "nerve tonic" to alleviate depression.
St John's wort
''Hypericum perforatum'', known as St. John's wort, is a flowering plant in the family Hypericaceae and the type species of the genus ''Hypericum''.
Possibly a hybrid between '' H. maculatum'' and '' H. attenuatum'', the species can be found a ...
fell out of favor in most countries through the 19th and 20th centuries, except in Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
, where Hypericum
''Hypericum'' is a genus of flowering plants in the family Hypericaceae (formerly considered a subfamily of Clusiaceae). The genus has a nearly worldwide distribution, missing only from tropical lowlands, deserts and polar regions. Many ''Hype ...
extracts were eventually licensed, packaged and prescribed. Small-scale efficacy trials were carried out in the 1970s and 1980s, and attention grew in the 1990s following a meta-analysis
A meta-analysis is a statistical analysis that combines the results of multiple scientific studies. Meta-analyses can be performed when there are multiple scientific studies addressing the same question, with each individual study reporting me ...
. It remains an over-the-counter drug
Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs
A prescription drug (also prescription medication or prescripti ...
(OTC) supplement in most countries. Of concern are lead contaminant; on average, lead levels in women in the United States taking St. John's wort are elevated about 20%. Research continues to investigate its active component hyperforin
Hyperforin is a phytochemical produced by some of the members of the plant genus '' Hypericum'', notably '' Hypericum perforatum'' (St John's wort). Hyperforin may be involved in the pharmacological effects of St. John's wort, specifically in its ...
, and to further understand its mode of action.
Isoniazid, iproniazid, and imipramine
In 1951, Irving Selikoff
Irving J. Selikoff (January 15, 1915 – May 20, 1992) was a medical researcher who in the 1960s established a link between the inhalation of asbestos particles and lung-related ailments. His work is largely responsible for the regulation of a ...
and Edward H. Robitzek, working out of Sea View Hospital on Staten Island
Staten Island ( ) is a borough of New York City, coextensive with Richmond County, in the U.S. state of New York. Located in the city's southwest portion, the borough is separated from New Jersey by the Arthur Kill and the Kill Van Kull an ...
, began clinical trials on two new anti-tuberculosis agents developed by Hoffman-LaRoche, Isoniazid
Isoniazid, also known as isonicotinic acid hydrazide (INH), is an antibiotic used for the treatment of tuberculosis. For active tuberculosis it is often used together with rifampicin, pyrazinamide, and either streptomycin or ethambutol. For l ...
and Iproniazid
Iproniazid (Marsilid, Rivivol, Euphozid, Iprazid, Ipronid, Ipronin) is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class. It is a xenobiotic that was originally designed to treat tuberculosis, but was lat ...
. Only patients with a poor prognosis
Prognosis (Greek: πρόγνωσις "fore-knowing, foreseeing") is a medical term for predicting the likely or expected development of a disease, including whether the signs and symptoms will improve or worsen (and how quickly) or remain stabl ...
were initially treated; nevertheless, their condition improved dramatically. Selikoff and Robitzek noted "a subtle general stimulation ... the patients exhibited renewed vigor and indeed this occasionally served to introduce disciplinary problems." The promise of a cure for tuberculosis in the Sea View Hospital trials was excitedly discussed in the mainstream press.
In 1952, learning of the stimulating side effects of Isoniazid, the Cincinnati psychiatrist Max Lurie tried it on his patients. In the following year, he and Harry Salzer reported that Isoniazid improved depression in two-thirds of their patients, so they then coined the term ''antidepressant'' to refer to its action. A similar incident took place in Paris, where Jean Delay, head of psychiatry at Sainte-Anne Hospital, heard of this effect from his pulmonology
Pulmonology (, , from Latin ''pulmō, -ōnis'' "lung" and the Greek suffix "study of"), pneumology (, built on Greek πνεύμων "lung") or pneumonology () is a medical specialty that deals with diseases involving the respiratory tract. ...
colleagues at Cochin Hospital. In 1952 (before Lurie and Salzer), Delay, with the resident Jean-Francois Buisson, reported the positive effect of isoniazid on depressed patients. The mode of antidepressant action of isoniazid is still unclear. It is speculated that its effect is due to the inhibition of Diamine Oxidase
Diamine oxidase (DAO), also known "amine oxidase, copper-containing, 1" (AOC1), formerly called histaminase, is an enzyme () involved in the metabolism, oxidation, and inactivation of histamine and other polyamines such as putrescine or spermid ...
, coupled with a weak inhibition of Monoamine Oxidase A
Monoamine oxidase A, also known as MAO-A, is an enzyme that in humans is encoded by the ''MAOA'' gene. This gene is one of two neighboring gene family members that encode mitochondrial enzymes which catalyze the oxidative deamination of amines, ...
.
Selikoff and Robitzek also experimented with another anti-tuberculosis drug, Iproniazid
Iproniazid (Marsilid, Rivivol, Euphozid, Iprazid, Ipronid, Ipronin) is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class. It is a xenobiotic that was originally designed to treat tuberculosis, but was lat ...
; it showed a greater psychostimulant effect, but more pronounced toxicity. Later, Jackson Smith, Gordon Kamman, George E. Crane, and Frank Ayd, described the psychiatric applications of Iproniazid. Ernst Zeller found Iproniazid to be a potent Monoamine oxidase inhibitor
Monoamine oxidase inhibitors (MAOIs) are a class of drugs that inhibit the activity of one or both monoamine oxidase enzymes: monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B). They are best known as effective antidepressants, espe ...
. Nevertheless, Iproniazid remained relatively obscure until Nathan S. Kline, the influential head of research at Rockland State Hospital
The Rockland Psychiatric Center, originally Rockland State Hospital, in Orangeburg, New York is a psychiatric facility for adults operated by the New York State Office of Mental Health. It offers in-patient and transitional treatment for adults, a ...
, began to popularize it in the medical and popular press as a "psychic energizer". Roche put a significant marketing effort behind Iproniazid. Its sales grew until it was recalled in 1961, due to reports of lethal hepatotoxicity
Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdrawn fro ...
.
The antidepressant effect of a Tricyclic
Tricyclics are chemical compounds that contain three interconnected rings of atoms.
Many compounds have a tricyclic structure, but in pharmacology, the term has traditionally been reserved to describe heterocyclic drugs. Among these are antid ...
, a three ringed compound, was first discovered in 1957 by Roland Kuhn
Roland Kuhn (4 March 1912 – 10 October 2005) was a Swiss psychiatrist who discovered that the drug imipramine had antidepressant properties. he was born in Biel and died in Scherzingen. In 1957, Kuhn published the results of his observations o ...
in a Swiss psychiatric hospital
Psychiatric hospitals, also known as mental health hospitals, behavioral health hospitals, are hospitals or wards specializing in the treatment of severe mental disorders, such as schizophrenia, bipolar disorder, eating disorders, dissociative ...
. Antihistamine
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ...
derivatives were used to treat surgical shock and later as neuroleptics
Antipsychotics, also known as neuroleptics, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but also in a range of oth ...
. Although in 1955, Reserpine
Reserpine is a drug that is used for the treatment of high blood pressure, usually in combination with a thiazide diuretic or vasodilator. Large clinical trials have shown that combined treatment with reserpine plus a thiazide diuretic reduces m ...
was shown to be more effective than placebo in alleviating anxious depression, neuroleptics were being developed as sedative
A sedative or tranquilliser is a substance that induces sedation by reducing irritability or excitement. They are CNS depressants and interact with brain activity causing its deceleration. Various kinds of sedatives can be distinguished, but t ...
s and antipsychotic
Antipsychotics, also known as neuroleptics, are a class of Psychiatric medication, psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizophrenia but ...
s.
Attempting to improve the effectiveness of Chlorpromazine
Chlorpromazine (CPZ), marketed under the brand names Thorazine and Largactil among others, is an antipsychotic medication. It is primarily used to treat psychotic disorders such as schizophrenia. Other uses include the treatment of bipolar dis ...
, Kuhn in conjunction with the Geigy
Novartis AG is a Swiss-American multinational pharmaceutical corporation based in Basel, Switzerland and
Cambridge, Massachusetts, United States (global research).name="novartis.com">https://www.novartis.com/research-development/research-loca ...
Pharmaceutical Company
The pharmaceutical industry discovers, develops, produces, and markets drugs or pharmaceutical drugs for use as medications to be administered to patients (or self-administered), with the aim to cure them, vaccinate them, or alleviate sympto ...
discovered the compound "G 22355", later renamed Imipramine
Imipramine, sold under the brand name Tofranil, among others, is a tricyclic antidepressant (TCA) mainly used in the treatment of depression. It is also effective in treating anxiety and panic disorder. The drug is also used to treat bedwetting. ...
. Imipramine had a beneficial effect in patients with depression who showed mental and motor retardation
Intellectual disability (ID), also known as general learning disability in the United Kingdom and formerly mental retardation,Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010). is a generalized neurodevelopmental disorder characterized by signifi ...
. Kuhn described his new compound as a "thymoleptic" "taking hold of the emotions," in contrast with neuroleptics, "taking hold of the nerves" in 1955–56. These gradually became established, resulting in the patent and manufacture in the US in 1951 by Häfliger and SchinderA.
Antidepressants became prescription drug
A prescription drug (also prescription medication or prescription medicine) is a pharmaceutical drug that legally requires a medical prescription to be dispensed. In contrast, over-the-counter drugs can be obtained without a prescription. The rea ...
s in the 1950s. It was estimated that no more than fifty to one hundred individuals per million had the kind of depression that these new drugs would treat, and pharmaceutical companies were not enthusiastic in marketing for this small market. Sales through the 1960s remained poor compared to the sales of tranquilizers, which were being marketed for different uses. Imipramine remained in common use and numerous successors were introduced. The use of monoamine oxidase inhibitors (MAOI) increased after the development and introduction of "reversible" forms affecting only the MAO-A subtype of inhibitors, making this drug safer to use.
By the 1960s, it was thought that the mode of action of Tricyclics was to inhibit norepinephrine reuptake. However, norepinephrine reuptake became associated with stimulating effects. Later Tricyclics were thought to affect serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
as proposed in 1969 by Carlsson and Lindqvist as well as Lapin and Oxenkrug.
Second generation antidepressants
Researchers began a process of rational drug design
Drug design, often referred to as rational drug design or simply rational design, is the inventive process of finding new medications based on the knowledge of a biological target. The drug is most commonly an organic small molecule that activa ...
to isolate antihistamine-derived compounds that would selectively target these systems. The first such compound to be patented was Zimelidine
Zimelidine (INN, BAN) (brand names Zimeldine, Normud, Zelmid) was one of the first selective serotonin reuptake inhibitor (SSRI) antidepressants to be marketed. It is a pyridylallylamine, and is structurally different from other antidepressants ...
in 1971, while the first released clinically was Indalpine
Indalpine (INN, BAN; brand name Upstène; developmental code name LM-5008) is a selective serotonin reuptake inhibitor (SSRI) class drug that was briefly marketed. It was discovered in 1977 by the pharmacologists Le Fur and Uzan at Pharmuka, a s ...
. Fluoxetine
Fluoxetine, sold under the brand names Prozac and Sarafem, among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used for the treatment of major depressive disorder, obsessive–compulsive disorde ...
was approved for commercial use by the US Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...
(FDA) in 1988, becoming the first blockbuster
Blockbuster or Block Buster may refer to:
*Blockbuster (entertainment) a term coined for an extremely successful movie, from which most other uses are derived.
Corporations
* Blockbuster (retailer), a defunct video and game rental chain
** Bl ...
SSRI. Fluoxetine was developed at Eli Lilly and Company
Eli Lilly and Company is an American pharmaceutical company headquartered in Indianapolis, Indiana, with offices in 18 countries. Its products are sold in approximately 125 countries. The company was founded in 1876 by, and named after, Colonel ...
in the early 1970s by Bryan Molloy
Bryan Barnet Molloy (30 March 1939 – 20 May 2004) was a Scottish chemist, known notably for helping to invent the antidepressant ''Prozac'', a name for fluoxetine. ''Prozac'' was introduced in 1988, and has been the world's leading antidepressan ...
, Klaus Schmiegel, David T. Wong and others. SSRIs became known as "novel antidepressants" along with other newer drugs such as SNRIs and NRIs with various selective effects.
Rapid-acting antidepressants
Esketamine
Esketamine, also known as (S)-ketamine or S(+)-ketamine, is the ''S''(+) enantiomer of ketamine, is a dissociative hallucinogen drug used as a general anesthetic and as an antidepressant for treatment of depression. It is sold under the brand ...
(brand name Spravato), the first rapid-acting antidepressant to be approved for clinical treatment of depression, was introduced for this indication in March 2019 in the United States.
Research
A 2016 randomized controlled trial
A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical te ...
evaluated the rapid antidepressant effects of the psychedelic Ayahuasca
AyahuascaPronounced as in the UK and in the US. Also occasionally known in English as ''ayaguasca'' (Spanish-derived), ''aioasca'' (Brazilian Portuguese-derived), or as ''yagé'', pronounced or . Etymologically, all forms but ''yagé'' descen ...
in treatment-resistant depression with positive outcome. In 2018, the FDA granted Breakthrough Therapy Designation for psilocybin
Psilocybin ( , ) is a naturally occurring psychedelic prodrug compound produced by more than 200 species of fungi. The most potent are members of the genus ''Psilocybe'', such as '' P. azurescens'', '' P. semilanceata'', and '' P.&nbs ...
-assisted therapy for treatment-resistant depression and in 2019, the FDA granted Breakthrough Therapy Designation for psilocybin therapy treating major depressive disorder.
Society and culture
Prescription trends
United Kingdom
In the UK, figures reported in 2010 indicated that the number of antidepressants prescribed by the National Health Service
The National Health Service (NHS) is the umbrella term for the publicly funded healthcare systems of the United Kingdom (UK). Since 1948, they have been funded out of general taxation. There are three systems which are referred to using the " ...
(NHS) almost doubled over a decade. Further analysis published in 2014 showed that number of antidepressants dispensed annually in the community went up by 25 million in the 14 years between 1998 and 2012, rising from 15 million to 40 million. Nearly 50% of this rise occurred in the four years after the 2008 banking crash, during which time the annual increase in prescriptions rose from 6.7% to 8.5%. These sources also suggest that aside from the recession, other factors that may influence changes in prescribing rates may include: improvements in diagnosis, a reduction of the stigma surrounding mental health, broader prescribing trends, GP characteristics, geographical location and housing status. Another factor that may contribute to increasing consumption of antidepressants is the fact that these medications now are used for other conditions including social anxiety
Social anxiety is the anxiety and fear specifically linked to being in social settings (i.e., interacting with others). Some categories of disorders associated with social anxiety include anxiety disorders, mood disorders, autism spectrum disord ...
and posttraumatic stress disorder
Post-traumatic stress disorder (PTSD) is a mental and behavioral disorder that can develop because of exposure to a traumatic event, such as sexual assault, warfare, traffic collisions, child abuse, domestic violence, or other threats on ...
.
Between 2005 and 2017, the number of adolescents (12 to 17 years) in England who were prescribed antidepressants has doubled. On the other hand, antidepressant prescriptions for children aged 5-11 in England decreased between 1999 and 2017. From April 2015, prescription increased for both age groups (for people aged 0 to 17) and peaked during the first COVID lockdown in March 2020.
According to National Institute for Health and Care Excellence
The National Institute for Health and Care Excellence (NICE) is an executive non-departmental public body of the Department of Health and Social Care in England that publishes guidelines in four areas:
* the use of health technologies withi ...
(NICE) guidelines, antidepressants for children and adolescents with depression and obsessive compulsive disorder (OCD) should be prescribed together with therapy and after being assessed by a child and adolescent psychiatrist. However, between 2006 and 2017, only 1 in 4 of 12-17 year olds who were prescribed an SSRI by their GP had seen a specialist psychiatrist and 1 in 6 has seen a paediatrician. Half of these prescriptions were for depression and 16% for anxiety, the latter not being licensed for treatment with antidepressants. Among the suggested possible reasons why GPs are not following the guidelines are the difficulties of accessing talking therapies, long waiting lists and the urgency of treatment. According to some researchers, strict adherence to treatment guidelines would limit access to effective medication for young people with mental health problems.
United States
In the United States, antidepressants were the most commonly prescribed medication in 2013. Of the estimated 16 million "long term" (over 24 months) users, roughly 70 percent are female. , about 16.5% of white people in the United States took antidepressants compared with 5.6% of black people in the United States.
United States: The most commonly prescribed antidepressants in the US retail market in 2010 were:
Netherlands: In the Netherlands, paroxetine
Paroxetine, sold under the brand names Paxil and Seroxat among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive-compulsive disorder, panic disorder ...
is the most prescribed antidepressant, followed by amitriptyline
Amitriptyline, sold under the brand name Elavil among others, is a tricyclic antidepressant primarily used to treat cyclic vomiting syndrome (CVS), major depressive disorder and a variety of pain syndromes from neuropathic pain to fibromyalgi ...
, citalopram
Citalopram, sold under the brand name Celexa among others, is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. It is used to treat major depressive disorder, obsessive compulsive disorder, panic disorder, and socia ...
and venlafaxine
Venlafaxine, sold under the brand name Effexor among others, is an antidepressant medication of the serotonin-norepinephrine reuptake inhibitor (SNRI) class. It is used to treat major depressive disorder, generalized anxiety disorder, panic di ...
.
Adherence
, worldwide, 30% to 60% of people didn't follow their practitioner's instructions about taking their antidepressants, and in the US, it appeared that around 50% of people did not take their antidepressants as directed by their practitioner.
When people fail to take their antidepressants, there is a greater risk that the drug won't help, that symptoms get worse, that they miss work or are less productive at work, and that the person may be hospitalized.[ ]
Social science perspective
Some academics have highlighted the need to examine the use of antidepressants and other medical treatments in cross-cultural terms, due to the fact that various cultures prescribe and observe different manifestations, symptoms, meanings and associations of depression and other medical conditions within their populations. These cross-cultural discrepancies, it has been argued, then have implications on the perceived efficacy and use of antidepressants and other strategies in the treatment of depression in these different cultures. In India, antidepressants are largely seen as tools to combat marginality, promising the individual the ability to reintegrate into society through their use—a view and association not observed in the West.
Environmental impacts
Because most antidepressants function by inhibiting the reuptake of neurotransmitters serotonin, dopamine, and norepinephrine these drugs can interfere with natural neurotransmitter levels in other organisms impacted by indirect exposure. Antidepressants fluoxetine and sertraline have been detected in aquatic organisms residing in effluent dominated streams. The presence of antidepressants in surface waters and aquatic organisms has caused concern because ecotoxicological effects to aquatic organisms due to fluoxetine exposure have been demonstrated.
Coral reef fish have been demonstrated to modulate aggressive behavior through serotonin. Artificially increasing serotonin levels in crustaceans can temporarily reverse social status and turn subordinates into aggressive and territorial dominant males.
Exposure to Fluoxetine has been demonstrated to increase serotonergic activity in fish, subsequently reducing aggressive behavior. Perinatal exposure to Fluoxetine at relevant environmental concentrations has been shown to lead to significant modifications of memory processing in 1-month-old cuttlefish. This impairment may disadvantage cuttlefish and decrease their survival. Somewhat less than 10% of orally administered Fluoxetine is excreted from humans unchanged or as glucuronide
A glucuronide, also known as glucuronoside, is any substance produced by linking glucuronic acid to another substance via a glycosidic bond. The glucuronides belong to the glycosides.
Glucuronidation, the conversion of chemical compounds to glucur ...
.
See also
* Management of depression
Management of depression is the treatment of depression that may involve a number of different therapies: medications, behavior therapy, psychotherapy, and medical devices.
Depression is a symptom of some physical diseases; a side effect of some ...
* Depression in childhood and adolescence
Depression is a mental disorder characterized by prolonged unhappiness or irritability, accompanied by a constellation of somatic and cognitive signs and symptoms such as fatigue, apathy, sleep problems, loss of appetite, loss of engagement; lo ...
* Antidepressants in Japan
* Atypical antidepressant
An atypical antidepressant is any antidepressant medication that acts in a manner that is different from that of most other antidepressants. Atypical antidepressants include agomelatine, bupropion, iprindole, mianserin, mirtazapine, nefazod ...
* Depression and natural therapies
* List of investigational antidepressants
This is a list of investigational antidepressants, or antidepressants that are currently under development for clinical use in the treatment of mood disorders but are not yet approved. ''Chemical/generic names are listed first, with developmental ...
References
Further reading
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External links
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{{Authority control
Major depressive disorder
Drug classes defined by psychological effects