Epilepsy is a group of non-communicable
neurological disorders characterized by recurrent
epileptic seizure
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with los ...
s.
Epileptic seizures can vary from brief and nearly undetectable periods to long periods of vigorous shaking due to abnormal electrical activity in the brain.
[ These episodes can result in physical injuries, either directly such as ]broken bones
A bone fracture (abbreviated FRX or Fx, Fx, or #) is a medical condition in which there is a partial or complete break in the continuity of any bone in the body. In more severe cases, the bone may be broken into several fragments, known as a '' ...
or through causing accidents.[ In epilepsy, seizures tend to recur and may have no immediate underlying cause.][ Isolated seizures that are provoked by a specific cause such as poisoning are not deemed to represent epilepsy.][ People with epilepsy may be treated differently in various areas of the world and experience varying degrees of ]social stigma
Social stigma is the disapproval of, or discrimination against, an individual or group based on perceived characteristics that serve to distinguish them from other members of a society. Social stigmas are commonly related to culture, gender, ra ...
due to the alarming nature of their symptoms.[
The underlying mechanism of epileptic seizures is excessive and abnormal ]neuronal
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. No ...
activity in the cortex of the brain which can be observed in the electroencephalogram
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex ...
(EEG) of an individual. The reason this occurs in most cases of epilepsy is unknown (idiopathic
An idiopathic disease is any disease with an unknown cause or mechanism of apparent spontaneous origin. From Greek ἴδιος ''idios'' "one's own" and πάθος ''pathos'' "suffering", ''idiopathy'' means approximately "a disease of its own kin ...
); some cases occur as the result of brain injury
An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or o ...
, stroke, brain tumor
A brain tumor occurs when abnormal cells form within the brain. There are two main types of tumors: malignant tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and seconda ...
s, infections of the brain, or birth defects
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities can ...
through a process known as epileptogenesis Epileptogenesis is the gradual process by which a typical brain develops epilepsy. Epilepsy is a chronic condition in which seizures occur.
These changes to the brain occasionally cause neurons to fire in an abnormal, hypersynchronous manner, know ...
.[ Known ]genetic mutations
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitos ...
are directly linked to a small proportion of cases. The diagnosis involves ruling out other conditions that might cause similar symptoms, such as fainting
Syncope, commonly known as fainting, or passing out, is a loss of consciousness and muscle strength characterized by a fast onset, short duration, and spontaneous recovery. It is caused by a decrease in blood flow to the brain, typically from ...
, and determining if another cause of seizures is present, such as alcohol withdrawal
Alcohol withdrawal syndrome (AWS) is a set of symptoms that can occur following a reduction in alcohol use after a period of excessive use. Symptoms typically include anxiety, shakiness, sweating, vomiting, fast heart rate, and a mild fever. M ...
or electrolyte problems.[ This may be partly done by imaging the brain and performing blood tests.][ Epilepsy can often be confirmed with an EEG, but a normal test does not rule out the condition.]
Epilepsy that occurs as a result of other issues may be preventable.[ Seizures are controllable with medication in about 69% of cases;] inexpensive anti-seizure medications are often available.[ In those whose seizures do not respond to medication; surgery, ]neurostimulation
Neurostimulation is the purposeful modulation of the nervous system's activity using invasive (e.g. microelectrodes) or non-invasive means (e.g. transcranial magnetic stimulation or transcranial electric stimulation, tES, such as tDCS or trans ...
or dietary changes may then be considered. Not all cases of epilepsy are lifelong, and many people improve to the point that treatment is no longer needed.[
, about 50 million people have epilepsy.] Nearly 80% of cases occur in the developing world. In 2015, it resulted in 125,000 deaths, an increase from 112,000 in 1990. Epilepsy is more common in older people. In the developed world
A developed country (or industrialized country, high-income country, more economically developed country (MEDC), advanced country) is a sovereign state that has a high quality of life, developed economy and advanced technological infrastruct ...
, onset of new cases occurs most frequently in babies and the elderly. In the developing world, onset is more common in older children and young adults due to differences in the frequency of the underlying causes. About 5–10% of people will have an unprovoked seizure by the age of 80, with the chance of experiencing a second seizure rising to between 40% and 50%. In many areas of the world, those with epilepsy either have restrictions placed on their ability to drive or are not permitted to drive until they are free of seizures for a specific length of time. The word ''epilepsy'' is from Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...
ἐπιλαμβάνειν, "to seize, possess, or afflict".
Signs and symptoms
Epilepsy is characterized by a long-term risk of recurrent epileptic seizures
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with los ...
. These seizures may present in several ways depending on the parts of the brain involved and the person's age.
Seizures
The most common type (60%) of seizures are convulsive
A convulsion is a medical condition where the body muscles contract and relax rapidly and repeatedly, resulting in uncontrolled shaking. Because epileptic seizures typically include convulsions, the term ''convulsion'' is sometimes used as a s ...
which involve involuntary muscle contractions. Of these, one-third begin as generalized seizure
Generalized epilepsy is a form of epilepsy characterised by generalised seizures with no apparent cause. Generalized seizures, as opposed to focal seizures, are a type of seizure that impairs consciousness and distorts the electrical activity of ...
s from the start, affecting both hemispheres of the brain and impairing consciousness
Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scien ...
. Two-thirds begin as focal seizure
Focal seizures (also called partial seizures and localized seizures) are seizures which affect initially only one hemisphere of the brain. The brain is divided into two hemispheres, each consisting of four lobes – the frontal, temporal, parie ...
s (which affect one hemisphere of the brain) which may progress to generalized seizure
Generalized epilepsy is a form of epilepsy characterised by generalised seizures with no apparent cause. Generalized seizures, as opposed to focal seizures, are a type of seizure that impairs consciousness and distorts the electrical activity of ...
s. The remaining 40% of seizures are non-convulsive. An example of this type is the absence seizure, which presents as a decreased level of consciousness and usually lasts about 10 seconds.
Certain experiences, known as auras often precede focal seizure
Focal seizures (also called partial seizures and localized seizures) are seizures which affect initially only one hemisphere of the brain. The brain is divided into two hemispheres, each consisting of four lobes – the frontal, temporal, parie ...
s.[ The seizures can include sensory (visual, hearing, or smell), psychic, autonomic, and motor phenomena depending on which part of the brain is involved.] Muscle jerks may start in a specific muscle group and spread to surrounding muscle groups in which case it is known as a Jacksonian march. Automatisms may occur, which are non-consciously generated activities and mostly simple repetitive movements like smacking the lips or more complex activities such as attempts to pick up something.[
There are six main types of generalized seizures: tonic-clonic, tonic, clonic, ]myoclonic
Myoclonus is a brief, involuntary, irregular (lacking rhythm) twitching of a muscle or a group of muscles, different from clonus, which is rhythmic or regular. Myoclonus (myo "muscle", clonic "jerk") describes a medical sign and, generally, i ...
, absence, and atonic seizure An atonic seizure (also called drop seizure, akinetic seizure, astatic seizure, or drop attack) is a type of seizure that consists of partial or complete loss of muscle tone that is caused by temporary alterations in brain function. These seizures ...
s. They all involve loss of consciousness
Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scien ...
and typically happen without warning.
Tonic-clonic seizures occur with a contraction of the limbs followed by their extension and arching of the back which lasts 10–30 seconds (the tonic phase). A cry may be heard due to contraction of the chest muscles, followed by a shaking of the limbs in unison (clonic phase). Tonic seizures produce constant contractions of the muscles. A person often turns blue as breathing is stopped. In clonic seizures there is shaking of the limbs in unison. After the shaking has stopped it may take 10–30 minutes for the person to return to normal; this period is called the "postictal state
The postictal state is the altered state of consciousness after an epileptic seizure. It usually lasts between 5 and 30 minutes, but sometimes longer in the case of larger or more severe seizures, and is characterized by drowsiness, confusion, na ...
" or "postictal phase." Loss of bowel or bladder control may occur during a seizure. People experiencing a seizure may bite their tongue, either the tip or on the sides;[ in tonic-clonic seizure, bites to the sides are more common.] Tongue bites are also relatively common in psychogenic non-epileptic seizures
Psychogenic non-epileptic seizures (PNES) are events resembling an epileptic seizure, but without the characteristic electrical discharges associated with epilepsy. PNES fall under the category of disorders known as functional neurological disor ...
.[
Myoclonic seizures involve very brief spasms of muscles in either a few areas or all over.] These sometimes cause the person to fall, which can cause injury.[ Absence seizures can be subtle with only a slight turn of the head or eye blinking with impaired consciousness;][ typically, the person does not fall over and returns to normal right after it ends.] Atonic seizures involve losing muscle activity for greater than one second,[ typically occurring on both sides of the body.][ Rarer seizure types can cause involuntary unnatural laughter (gelastic), crying (dyscrastic), or more complex experiences such as '']déjà vu
''Déjà vu'' ( , ; "already seen") is a French loanword for the phenomenon of feeling as though one has lived through the present situation before.Schnider, Armin. (2008). ''The Confabulating Mind: How the Brain Creates Reality''. Oxford Univers ...
''.
About 6% of those with epilepsy have seizures that are often triggered by specific events and are known as reflex seizures. Those with reflex epilepsy
Reflex seizures are epileptic seizures that are consistently induced by a specific stimulus or trigger making them distinct from other epileptic seizures, which are usually unprovoked. Reflex seizures are otherwise similar to unprovoked seizures a ...
have seizures that are only triggered by specific stimuli. Common triggers include flashing lights and sudden noises.[ In certain types of epilepsy, seizures happen more often during ]sleep
Sleep is a sedentary state of mind and body. It is characterized by altered consciousness, relatively inhibited sensory activity, reduced muscle activity and reduced interactions with surroundings. It is distinguished from wakefulness by a de ...
, and in other types they occur almost only when sleeping.
Seizure clusters
Patients with epilepsy may experience seizure clusters which may be broadly defined as an acute deterioration in seizure control. The prevalence of seizure clusters is uncertain given that studies have used different definitions to define them. However, estimates suggest that the prevalence may range from 5% to 50% of epilepsy patients. Refractory epilepsy patients who have a high seizure frequency are at the greatest risk for having seizure clusters. Seizure clusters are associated with increased healthcare utilization, worse quality of life, impaired psychosocial functioning, and possibly increased mortality. Benzodiazepines are used as an acute treatment for seizure clusters.
Post-ictal
After the active portion of a seizure (the ictal state) there is typically a period of recovery during which there is confusion, referred to as the postictal period, before a normal level of consciousness
An altered level of consciousness is any measure of arousal other than normal. Level of consciousness (LOC) is a measurement of a person's arousability and responsiveness to stimuli from the environment.
A mildly depressed level of consciousn ...
returns.[ It usually lasts 3 to 15 minutes but may last for hours.][ Other common symptoms include feeling tired, headache, difficulty speaking, and abnormal behavior.] 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 ...
after a seizure is relatively common, occurring in 6–10% of people. Often people do not remember what happened during this time.[ Localized weakness, known as Todd's paralysis, may also occur after a focal seizure. It would typically last for seconds to minutes but may rarely last for a day or two.]
Psychosocial
Epilepsy can have adverse effects on social and psychological well-being. These effects may include social isolation, stigmatization, or disability. They may result in lower educational achievement and worse employment outcomes. Learning disabilities are common in those with the condition, and especially among children with epilepsy. The stigma of epilepsy can also affect the families of those with the disorder.[
Certain disorders occur more often in people with epilepsy, depending partly on the epilepsy syndrome present. These include depression, ]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 ...
, 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), and migraine. 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) affects three to five times more children with epilepsy than children without the condition. ADHD and epilepsy have significant consequences on a child's behavioral, learning, and social development. Epilepsy is also more common in children with autism.
Approximately, one-in-three people with epilepsy have a lifetime history of a psychiatric disorder. There are believed to be multiple causes for this including pathophysiological changes related to the epilepsy itself as well as adverse experiences related to living with epilepsy (e.g., stigma, discrimination). In addition, it is thought that the relationship between epilepsy and psychiatric disorders is not unilateral but rather bidirectional. For example, patients with depression have an increased risk for developing new-onset epilepsy.
The presence of comorbid depression or anxiety in patients with epilepsy is associated with a poorer quality of life, increased mortality, increased healthcare utilization and a worse response to treatment (including surgical). Anxiety disorders and depression may explain more variability in quality of life than seizure type or frequency. There is evidence that both depression and anxiety disorders are underdiagnosed and undertreated in patients with epilepsy.
Causes
Epilepsy can have both genetic and acquired causes, with the interaction of these factors in many cases.[ Established acquired causes include serious brain trauma, stroke, tumours, and brain problems resulting from a previous ]infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable dis ...
. In about 60% of cases, the cause is unknown.[ Epilepsies caused by genetic, congenital, or ]developmental
Development of the human body is the process of growth to maturity. The process begins with fertilization, where an egg released from the ovary of a female is penetrated by a sperm cell from a male. The resulting zygote develops through mitosi ...
conditions are more common among younger people, while brain tumor
A brain tumor occurs when abnormal cells form within the brain. There are two main types of tumors: malignant tumors and benign (non-cancerous) tumors. These can be further classified as primary tumors, which start within the brain, and seconda ...
s and strokes
A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop funct ...
are more likely in older people.
Seizures may also occur as a consequence of other health problems; if they occur right around a specific cause, such as a stroke, head injury, toxic ingestion, or metabolic problem, they are known as acute symptomatic seizures and are in the broader classification of seizure-related disorders rather than epilepsy itself.[
]
Genetics
Genetics is believed to be involved in the majority of cases, either directly or indirectly.[ Some epilepsies are due to a single gene defect (1–2%); most are due to the interaction of multiple genes and environmental factors.][ Each of the single gene defects is rare, with more than 200 in all described. Most genes involved affect ion channels, either directly or indirectly.][ These include genes for ion channels themselves, ]enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
s, GABA, and G protein-coupled receptor
G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...
s.
In identical twins
Twins are two offspring produced by the same pregnancy.MedicineNet > Definition of TwinLast Editorial Review: 19 June 2000 Twins can be either ''monozygotic'' ('identical'), meaning that they develop from one zygote, which splits and forms two em ...
, if one is affected, there is a 50–60% chance that the other will also be affected.[ In non-identical twins, the risk is 15%.][ These risks are greater in those with generalized rather than focal seizures.][ If both twins are affected, most of the time they have the same epileptic syndrome (70–90%).][ Other close relatives of a person with epilepsy have a risk five times that of the general population.] Between 1 and 10% of those with Down syndrome
Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is usually associated with physical growth delays, mild to moderate intellectual dis ...
and 90% of those with Angelman syndrome have epilepsy.[
]
Phakomatoses
Phakomatoses, also known as neurocutaneous disorders, are a group of multisystemic diseases that most prominently affect the skin and central nervous system. They are caused by defective development of the embryonic ectodermal tissue that is most often due to a single genetic mutation. The brain, as well as other neural tissue and the skin, are all derived from the ectoderm and thus defective development may result in epilepsy as well as other manifestations such as autism and intellectual disability. Some types of phakomatoses such as tuberous sclerosis complex and Sturge-Weber syndrome have a higher prevalence of epilepsy relative to others such as neurofibromatosis type 1.
Tuberous sclerosis complex
Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant genetic disease that causes non-cancerous tumours to grow in the brain and on other vital organs such as the kidneys, heart, liver, eyes, lungs and skin. A combination ...
is an autosomal dominant disorder that is caused by mutations in either the TSC1
Tuberous sclerosis 1 (TSC1), also known as hamartin, is a protein that in humans is encoded by the ''TSC1'' gene.
Function
TSC1 functions as a co-chaperone which inhibits the ATPase activity of the chaperone Hsp90 (heat shock protein-90) and de ...
or TSC2
Tuberous Sclerosis Complex 2 (TSC2), also known as Tuberin, is a protein that in humans is encoded by the ''TSC2'' gene.
Function
Mutations in this gene lead to tuberous sclerosis. Its gene product is believed to be a tumor suppressor and is a ...
gene and it affects approximately 1 in 6,000-10,000 live births. These mutations result in the upregulation of the mechanistic target of rapamycin (mTOR) pathway which leads to the growth of tumors in many organs including the brain, skin, heart, eyes and kidneys. In addition, abnormal mTOR activity is believed to alter neural excitability. The prevalence of epilepsy is estimated to be 80-90%. The majority of cases of epilepsy present within the first 3 years of life and are medically refractory. Relatively recent developments for the treatment of epilepsy in TSC patients include mTOR inhibitors
mTOR inhibitors are a class of drugs that inhibit the mechanistic target of rapamycin (mTOR), which is a serine/threonine-specific protein kinase that belongs to the family of phosphatidylinositol-3 kinase (PI3K) related kinases (PIKKs). mTOR re ...
, cannabidiol and vigabatrin. Epilepsy surgery is often pursued.
Sturge-Weber syndrome is caused by an activating somatic mutation in the GNAQ
Guanine nucleotide-binding protein G(q) subunit alpha is a protein that in humans is encoded by the ''GNAQ'' gene. Together with GNA11 (its paralogue), it functions as a Gq alpha subunit.
Function
Guanine nucleotide-binding proteins are a fam ...
gene and it affects approximately 1 in 20,000-50,000 live births. The mutation results in vascular malformations affecting the brain, skin and eyes. The typical presentation includes a facial port-wine birthmark, ocular angiomas and cerebral vascular malformations which are most often unilateral but are bilateral in 15% of cases. The prevalence of epilepsy is 75-100% and is higher in those with bilateral involvement. Seizures typically occur within the first two years of life and are refractory in nearly half of cases. However, high rates of seizure freedom with surgery have been reported in as many as 83%.
Neurofibromatosis type 1
Neurofibromatosis (NF) is a group of three conditions in which tumors grow in the nervous system. The three types are neurofibromatosis type I (NF1), neurofibromatosis type II (NF2), and schwannomatosis. In NF1 symptoms include light brown sp ...
is the most common phakomatoses and occurs in approximately 1 in 3,000 live births. It is caused by autosomal dominant mutations in the Neurofibromin 1
Neurofibromin 1 (''NF1'') is a gene in humans that is located on chromosome 17. ''NF1'' codes for neurofibromin, a GTPase-activating protein that negatively regulates RAS/MAPK pathway activity by accelerating the hydrolysis of Ras-bound GTP. ' ...
gene. Clinical manifestations are variable but may include hyperpigmented skin marks, hamartomas of the iris called Lisch nodules, neurofibroma
A neurofibroma is a benign nerve-sheath tumor in the peripheral nervous system. In 90% of cases, they are found as stand-alone tumors (solitary neurofibroma, solitary nerve sheath tumor or sporadic neurofibroma), while the remainder are found in p ...
s, optic pathway gliomas and cognitive impairment. The prevalence of epilepsy is estimated to be 4-7%. Seizures are typically easier to control with anti-seizure medications relative to other phakomatoses but in some refractory cases surgery may need to be pursued.
Acquired
Epilepsy may occur as a result of several other conditions, including tumors, strokes, head trauma, previous infections of the central nervous system, genetic abnormalities, and as a result of brain damage around the time of birth.[ Of those with brain tumors, almost 30% have epilepsy, making them the cause of about 4% of cases.][ The risk is greatest for tumors in the ]temporal lobe
The temporal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain.
The temporal lobe is involved in pro ...
and those that grow slowly.[ Other mass lesions such as cerebral cavernous malformations and ]arteriovenous malformations
Arteriovenous malformation is an abnormal connection between arteries and veins, bypassing the capillary system. This vascular anomaly is widely known because of its occurrence in the central nervous system (usually cerebral AVM), but can app ...
have risks as high as 4060%.[ Of those who have had a stroke, 6–10% develop epilepsy. Risk factors for post-stroke epilepsy include stroke severity, cortical involvement, hemorrhage and early seizures. Between 6 and 20% of epilepsy is believed to be due to head trauma.][ Mild brain injury increases the risk about two-fold while severe brain injury increases the risk seven-fold.][ In those who have experienced a high-powered gunshot wound to the head, the risk is about 50%.][
Some evidence links epilepsy and ]celiac disease
Coeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine, where individuals develop intolerance to gluten, present in foods such as wheat, rye and barle ...
and non-celiac gluten sensitivity
Non-celiac gluten sensitivity (NCGS) or gluten sensitivity is "a clinical entity induced by the ingestion of gluten leading to intestinal and/or extraintestinal symptoms that improve once the gluten-containing foodstuff is removed from the diet, a ...
, while other evidence does not. There appears to be a specific syndrome that includes coeliac disease, epilepsy, and calcifications in the brain. A 2012 review estimates that between 1% and 6% of people with epilepsy have coeliac disease while 1% of the general population has the condition.
The risk of epilepsy following meningitis is less than 10%; it more commonly causes seizures during the infection itself.[ In ]herpes simplex encephalitis
Herpesviral encephalitis, or herpes simplex encephalitis (HSE), is encephalitis due to herpes simplex virus. It is estimated to affect at least 1 in 500,000 individuals per year, and some studies suggest an incidence rate of 5.9 cases per 100,00 ...
the risk of a seizure is around 50%[ with a high risk of epilepsy following (up to 25%). A form of an infection with the ]pork tapeworm
''Taenia solium'', the pork tapeworm, belongs to the cyclophyllid cestode family Taeniidae. It is found throughout the world and is most common in countries where pork is eaten. It is a tapeworm that uses humans as its definitive host and pigs ...
(cysticercosis
Cysticercosis is a tissue infection caused by the young form of the pork tapeworm. People may have few or no symptoms for years. In some cases, particularly in Asia, solid lumps of between one and two centimetres may develop under the skin. Aft ...
), in the brain, is known as neurocysticercosis, and is the cause of up to half of epilepsy cases in areas of the world where the parasite is common.[ Epilepsy may also occur after other brain infections such as ]cerebral malaria
Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects humans and other animals. Malaria causes Signs and symptoms, symptoms that typically include fever, fatigue (medical), tiredness, vomiting, and headaches. In se ...
, toxoplasmosis
Toxoplasmosis is a parasitic disease caused by '' Toxoplasma gondii'', an apicomplexan. Infections with toxoplasmosis are associated with a variety of neuropsychiatric and behavioral conditions. Occasionally, people may have a few weeks or mont ...
, and toxocariasis
Toxocariasis is an illness of humans caused by the dog roundworm ('' Toxocara canis'') and, less frequently, the cat roundworm (''Toxocara cati'').https://academic.oup.com/ajcp/article/142/suppl_1/A104/1771175 Eosinophilic Pseudoleukemia Due to T ...
.[ Chronic alcohol use increases the risk of epilepsy: those who drink six ]units of alcohol
Units of alcohol are used in the United Kingdom (UK) as a measure to quantify the actual alcoholic content within a given volume of an alcoholic beverage, in order to provide guidance on total alcohol consumption.
A number of other countries (i ...
per day have a 2.5-fold increase in risk.[ Other risks include Alzheimer's disease, multiple sclerosis, tuberous sclerosis, and ]autoimmune encephalitis
Autoimmune encephalitis (AIE) is a type of encephalitis, and one of the most common causes of noninfectious encephalitis. It can be triggered by tumors, infections, or it may be cryptogenic. The neurological manifestations can be either acute o ...
.[ Getting vaccinated does not increase the risk of epilepsy.][ ]Malnutrition
Malnutrition occurs when an organism gets too few or too many nutrients, resulting in health problems. Specifically, it is "a deficiency, excess, or imbalance of energy, protein and other nutrients" which adversely affects the body's tissues ...
is a risk factor seen mostly in the developing world, although it is unclear however if it is a direct cause or an association.[ People with ]cerebral palsy
Cerebral palsy (CP) is a group of movement disorders that appear in early childhood. Signs and symptoms vary among people and over time, but include poor coordination, stiff muscles, weak muscles, and tremors. There may be problems with sens ...
have an increased risk of epilepsy, with half of people with spastic quadriplegia
Spastic quadriplegia, also known as spastic tetraplegia, is a subset of spastic cerebral palsy that affects all four limbs (both arms and legs).
Compared to quadriplegia, spastic tetraplegia is defined by spasticity of the limbs as opposed to ...
and spastic hemiplegia having the disease.
Mechanism
Normally brain electrical activity is non-synchronous, as large numbers of neurons do not normally fire at the same time, but rather fire in order as signals travel throughout the brain. Neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. ...
activity is regulated by various factors both within the cell and the cellular environment. Factors within the neuron include the type, number and distribution of ion channels, changes to receptors
Receptor may refer to:
*Sensory receptor, in physiology, any structure which, on receiving environmental stimuli, produces an informative nerve impulse
*Receptor (biochemistry), in biochemistry, a protein molecule that receives and responds to a n ...
and changes of gene expression.[ Factors around the neuron include ]ion
An ion () is an atom or molecule with a net electrical charge.
The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...
concentrations, synaptic plasticity
In neuroscience, synaptic plasticity is the ability of synapses to strengthen or weaken over time, in response to increases or decreases in their activity. Since memories are postulated to be represented by vastly interconnected neural circuits ...
and regulation of transmitter
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to the ...
breakdown by glial cells
Glia, also called glial cells (gliocytes) or neuroglia, are non-neuronal cells in the central nervous system (brain and spinal cord) and the peripheral nervous system that do not produce electrical impulses. They maintain homeostasis, form myel ...
.
Epilepsy
The exact mechanism for epilepsy is unknown, but a little is known about its cellular and network mechanisms. However, it is unknown under which circumstances the brain shifts into the activity of a seizure with its excessive synchronization. Changes in MicroRNAs (miRNAs) levels seems to play a leading role. MicroRNAs (miRNAs) are a family of small non-coding RNAs that control the expression levels of multiple proteins by decreasing mRNA stability and translation, and could therefore be key regulatory mechanisms and therapeutic targets in epilepsy
In epilepsy, the resistance of excitatory neurons to fire during this period is decreased.[ This may occur due to changes in ion channels or inhibitory neurons not functioning properly.][ This then results in a specific area from which seizures may develop, known as a "seizure focus".][ Another mechanism of epilepsy may be the up-regulation of excitatory circuits or down-regulation of inhibitory circuits following an injury to the brain.][ These secondary epilepsies occur through processes known as ]epileptogenesis Epileptogenesis is the gradual process by which a typical brain develops epilepsy. Epilepsy is a chronic condition in which seizures occur.
These changes to the brain occasionally cause neurons to fire in an abnormal, hypersynchronous manner, know ...
. Failure of the blood–brain barrier may also be a causal mechanism as it would allow substances in the blood to enter the brain.
Seizures
There is evidence that epileptic seizures
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with los ...
are usually not a random event. Seizures are often brought on by factors (also known as triggers) such as stress, excessive alcohol use, flickering light, or a lack of sleep, among others. The term seizure threshold is used to indicate the amount of stimulus
A stimulus is something that causes a physiological response. It may refer to:
*Stimulation
**Stimulus (physiology), something external that influences an activity
**Stimulus (psychology), a concept in behaviorism and perception
*Stimulus (economi ...
necessary to bring about a seizure; this threshold is lowered in epilepsy.[
In epileptic seizures a group of neurons begin firing in an abnormal, excessive,] and synchronized manner. This results in a wave of depolarization known as a paroxysmal depolarizing shift. Normally, after an excitatory neuron fires it becomes more resistant to firing for a period of time.[ This is due in part to the effect of inhibitory neurons, electrical changes within the excitatory neuron, and the negative effects of adenosine.][
Focal seizures begin in one area of the brain while generalized seizures begin in both hemispheres.] Some types of seizures may change brain structure, while others appear to have little effect. Gliosis
Gliosis is a nonspecific reactive change of glial cells in response to damage to the central nervous system (CNS). In most cases, gliosis involves the proliferation or hypertrophy of several different types of glial cells, including astrocytes, ...
, neuronal loss, and atrophy of specific areas of the brain are linked to epilepsy but it is unclear if epilepsy causes these changes or if these changes result in epilepsy.[
The seizures can be described on different scales, from the cellular level to the whole brain. These are several concomitant factor, which on different scale can "drive" the brain to pathological states and trigger a seizure.
]
Diagnosis
The diagnosis of epilepsy is typically made based on observation of the seizure onset and the underlying cause. An electroencephalogram
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex ...
(EEG) to look for abnormal patterns of brain waves and neuroimaging
Neuroimaging is the use of quantitative (computational) techniques to study the structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive manner. Incr ...
( CT scan or MRI
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...
) to look at the structure of the brain are also usually part of the initial investigations. While figuring out a specific epileptic syndrome is often attempted, it is not always possible. Video and EEG monitoring may be useful in difficult cases.
Definition
Epilepsy is a disorder of the brain defined by any of the following conditions:[
:
Furthermore, epilepsy is considered to be resolved for individuals who had an age-dependent epilepsy syndrome but are now past that age or those who have remained seizure-free for the last 10 years, with no seizure medicines for the last 5 years.][
This 2014 definition of the ]International League Against Epilepsy The International League Against Epilepsy was started in 1909. Its goal is to improve the lives of people with epilepsy through research.
They run the medical journals ''Epilepsia'', ''Epilepsia Open'', and ''Epileptic Disorders
''Epileptic Disor ...
[ is a clarification of the ILAE 2005 conceptual definition, according to which epilepsy is "a disorder of the brain characterized by an enduring predisposition to generate epileptic seizures and by the neurobiologic, cognitive, psychological, and social consequences of this condition. The definition of epilepsy requires the occurrence of at least one epileptic seizure."]
It is, therefore, possible to outgrow epilepsy or to undergo treatment that causes epilepsy to be resolved, but with no guarantee that it will not return. In the definition, epilepsy is now called a disease, rather than a disorder. This was a decision of the executive committee of the ILAE, taken because the word "disorder," while perhaps having less stigma than does "disease," also does not express the degree of seriousness that epilepsy deserves.[
The definition is practical in nature and is designed for clinical use. In particular, it aims to clarify when an "enduring predisposition" according to the 2005 conceptual definition is present. Researchers, statistically minded epidemiologists, and other specialized groups may choose to use the older definition or a definition of their own devising. The ILAE considers doing so is perfectly allowable, so long as it is clear what definition is being used.][
]
Classification
In contrast to the classification of seizures which focuses on what happens during a seizure, the classification of epilepsies focuses on the underlying causes. When a person is admitted to hospital after an epileptic seizure the diagnostic workup
Medical diagnosis (abbreviated Dx, Dx, or Ds) is the process of determining which disease or condition explains a person's symptoms and signs. It is most often referred to as diagnosis with the medical context being implicit. The information re ...
results preferably in the seizure itself being classified (e.g. tonic-clonic) and in the underlying disease being identified (e.g. hippocampal sclerosis
Hippocampal sclerosis (HS) or mesial temporal sclerosis (MTS) is a neuropathological condition with severe neuronal cell loss and gliosis in the hippocampus, specifically in the CA-1 (Cornu Ammonis area 1) and subiculum of the hippocampus. It w ...
). The name of the diagnosis finally made depends on the available diagnostic results and the applied definitions and classifications (of seizures and epilepsies) and its respective terminology.
The International League Against Epilepsy The International League Against Epilepsy was started in 1909. Its goal is to improve the lives of people with epilepsy through research.
They run the medical journals ''Epilepsia'', ''Epilepsia Open'', and ''Epileptic Disorders
''Epileptic Disor ...
(ILAE) provided a classification of the epilepsies and epileptic syndromes in 1989 as follows:
:
This classification was widely accepted but has also been criticized mainly because the underlying causes of epilepsy (which are a major determinant of clinical course and prognosis) were not covered in detail. In 2010 the ILAE Commission for Classification of the Epilepsies addressed this issue and divided epilepsies into three categories (genetic, structural/metabolic, unknown cause) that were refined in their 2011 recommendation into four categories and a number of subcategories reflecting recent technologic and scientific advances.
: A revised, operational classification of seizure types has been introduced by the ILAE. It allows more clearly understood terms and clearly defines focal and generalized onset dichotomy, when possible, even without observing the seizures based on description by patient or observers. The essential changes in terminology are that "partial" is called "focal" with awareness used as a classifier for focal seizures -based on description focal seizures are now defined as behavioral arrest, automatisms, cognitive, autonomic, emotional or hyperkinetic variants while atonic, myoclonic, clonic, infantile spasms, and tonic seizures may be either focal or generalized based on their onset. Several terms that were not clear or consistent in description were removed such as dyscognitive, psychic, simple and complex partial, while "secondarily generalized" is replaced by a clearer term "focal to bilateral tonic clonic seizure". New seizure types now believed to be generalized are eyelid myoclonia, myoclonic atonic, myoclonic absence, and myoclonic tonic clonic. Sometimes it is possible to classify seizures as focal or generalized based on presenting features even though onset in not known. This system is based on the 1981 seizure classification modified in 2010 and principally is the same with an effort to improve the flexibility and clarity of use to understand seizures types better in keeping with current knowledge.
Syndromes
Cases of epilepsy may be organized into epilepsy syndromes People with epilepsy may be classified into different syndromes based on specific clinical features. These features include the age at which seizures begin, the seizure types, and EEG findings, among others. Identifying an epilepsy syndrome is usefu ...
by the specific features that are present. These features include the age that seizure begin, the seizure types, EEG
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex ...
findings, among others. Identifying an epilepsy syndrome is useful as it helps determine the underlying causes as well as what anti-seizure medication
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 ...
should be tried.
The ability to categorize a case of epilepsy into a specific syndrome occurs more often with children since the onset of seizures is commonly early.[ Less serious examples are benign rolandic epilepsy (2.8 per 100,000), ]childhood absence epilepsy
Childhood absence epilepsy (CAE), is one of the most frequent pediatric epilepsy syndromes. CAE is an idiopathic generalized epilepsy that occurs in otherwise normal children. The only seizure type at the time of diagnosis is the typical absence s ...
(0.8 per 100,000) and juvenile myoclonic epilepsy (0.7 per 100,000).[ Severe syndromes with diffuse brain dysfunction caused, at least partly, by some aspect of epilepsy, are also referred to as developmental and epileptic encephalopathies. These are associated with frequent ]seizures
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with l ...
that are resistant to treatment and cognitive dysfunction, for instance Lennox–Gastaut syndrome
Lennox–Gastaut syndrome (LGS) is a complex, rare, and severe childhood-onset epilepsy. It is characterized by multiple and concurrent seizure types, cognitive dysfunction, and slow spike waves on electroencephalogram (EEG). Typically, it presents ...
(1-2% of all persons with epilepsy), Dravet syndrome
Dravet syndrome, previously known as severe myoclonic epilepsy of infancy (SMEI), is an autosomal dominant genetic disorder which causes a catastrophic form of epilepsy, with prolonged seizures that are often triggered by hot temperatures or feve ...
(1: 15000-40000 worldwide), and West syndrome(1-9: 100000). Genetics is believed to play an important role in epilepsies by a number of mechanisms. Simple and complex modes of inheritance
Inheritance is the practice of receiving private property, titles, debts, entitlements, privileges, rights, and obligations upon the death of an individual. The rules of inheritance differ among societies and have changed over time. Officia ...
have been identified for some of them. However, extensive screening have failed to identify many single gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
variants of large effect. More recent exome and genome sequencing studies have begun to reveal a number of de novo gene mutations that are responsible for some epileptic encephalopathies, including CHD2
Chromodomain-helicase-DNA-binding protein 2 is an enzyme that in humans is encoded by the ''CHD2'' gene.
Function
The CHD family of proteins is characterized by the presence of chromo (chromatin organization modifier) domains and SNF2-relate ...
and SYNGAP1
Synaptic Ras GTPase-activating protein 1, also known as synaptic Ras-GAP 1 or SYNGAP1, is a protein that in humans is encoded by the ''SYNGAP1'' gene. SYNGAP1 is a ras GTPase-activating protein that is critical for the development of cognition a ...
and DNM1
Dynamin-1 is a protein that in humans is encoded by the ''DNM1'' gene.
Function
This gene encodes a member of the dynamin subfamily of GTP-binding proteins. The encoded protein possesses unique mechanochemical properties used to tubulate and s ...
, GABBR2, FASN and RYR3
Ryanodine receptor 3 is one of a class of ryanodine receptors and a protein that in humans is encoded by the ''RYR3'' gene. The protein encoded by this gene is both a calcium channel and a receptor for the plant alkaloid ryanodine. RYR3 and RY ...
.
Syndromes in which causes are not clearly identified are difficult to match with categories of the current classification of epilepsy. Categorization for these cases was made somewhat arbitrarily. The ''idiopathic'' (unknown cause) category of the 2011 classification includes syndromes in which the general clinical features and/or age specificity strongly point to a presumed genetic cause. Some childhood epilepsy syndromes are included in the unknown cause category in which the cause is presumed genetic, for instance benign rolandic epilepsy. Others are included in ''symptomatic'' despite a presumed genetic cause (in at least in some cases), for instance Lennox-Gastaut syndrome. Clinical syndromes in which epilepsy is not the main feature (e.g. Angelman syndrome) were categorized ''symptomatic'' but it was argued to include these within the category ''idiopathic''. Classification of epilepsies and particularly of epilepsy syndromes will change with advances in research.
Tests
An electroencephalogram
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex ...
(EEG) can assist in showing brain activity suggestive of an increased risk of seizures. It is only recommended for those who are likely to have had an epileptic seizure on the basis of symptoms. In the diagnosis of epilepsy, electroencephalography may help distinguish the type of seizure or syndrome present. In children it is typically only needed after a second seizure unless specified by a specialist. It cannot be used to rule out the diagnosis and may be falsely positive in those without the disease. In certain situations it may be useful to perform the EEG while the affected individual is sleeping or sleep deprived.
Diagnostic imaging by CT scan and MRI
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...
is recommended after a first non-febrile seizure to detect structural problems in and around the brain. MRI is generally a better imaging test except when bleeding is suspected, for which CT is more sensitive and more easily available.[ If someone attends the emergency room with a seizure but returns to normal quickly, imaging tests may be done at a later point.][ If a person has a previous diagnosis of epilepsy with previous imaging, repeating the imaging is usually not needed even if there are subsequent seizures.][
For adults, the testing of electrolyte, ]blood glucose
Glycaemia, also known as blood sugar level, blood sugar concentration, or blood glucose level is the measure of glucose concentrated in the blood of humans or other animals. Approximately 4 grams of glucose, a simple sugar, is present in the blo ...
and calcium levels is important to rule out problems with these as causes. An electrocardiogram can rule out problems with the rhythm of the heart. A lumbar puncture may be useful to diagnose a central nervous system
The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all p ...
infection but is not routinely needed.[ In children additional tests may be required such as urine biochemistry and blood testing looking for ]metabolic disorder
A metabolic disorder is a disorder that negatively alters the body's processing and distribution of macronutrients, such as proteins, fats, and carbohydrates. Metabolic disorders can happen when abnormal chemical reactions in the body alter t ...
s. Together with EEG and neuroimaging, genetic testing is becoming one of the most important diagnostic technique for epilepsy, as a diagnosis might be achieved in a relevant proportion of cases with severe epilepsies, both in children and adults. For those with negative genetic testing, in some it might be important to repeat or re-analyze previous genetic studies after 2–3 years.
A high blood 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 ...
level within the first 20 minutes following a seizure may be useful to help confirm an epileptic seizure as opposed to psychogenic non-epileptic seizure
Psychogenic non-epileptic seizures (PNES) are events resembling an epileptic seizure, but without the characteristic electrical discharges associated with epilepsy. PNES fall under the category of disorders known as functional neurological disor ...
. Serum prolactin level is less useful for detecting focal seizures. If it is normal an epileptic seizure is still possible[ and a serum prolactin does not separate epileptic seizures from syncope.] It is not recommended as a routine part of the diagnosis of epilepsy.
Differential diagnosis
Diagnosis of epilepsy can be difficult. A number of other conditions may present very similar signs and symptoms to seizures, including syncope, hyperventilation, migraines, 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 affect ...
, panic attack
Panic attacks are sudden periods of intense fear and discomfort that may include palpitations, sweating, chest pain or chest discomfort, shortness of breath, trembling, dizziness, numbness, confusion, or a feeling of impending doom or of losing ...
s and psychogenic non-epileptic seizures
Psychogenic non-epileptic seizures (PNES) are events resembling an epileptic seizure, but without the characteristic electrical discharges associated with epilepsy. PNES fall under the category of disorders known as functional neurological disor ...
(PNES).[ In particular a syncope can be accompanied by a short episode of convulsions.] Nocturnal frontal lobe epilepsy, often misdiagnosed as nightmares, was considered to be a parasomnia
Parasomnias are a category of sleep disorders that involve abnormal movements, behaviors, emotions, perceptions, and dreams that occur while falling asleep, sleeping, between sleep stages, or during arousal from sleep. Parasomnias are dissociat ...
but later identified to be an epilepsy syndrome. Attacks of the movement disorder paroxysmal dyskinesia
The paroxysmal dyskinesias (PD) are a group of movement disorders characterized by attacks of hyperkinesia with intact consciousness. Paroxysmal dyskinesia is a rare disorder, however the number of individuals it affects remains unclear. There are ...
may be taken for epileptic seizures. The cause of a drop attack A drop attack is a sudden fall without loss of consciousness. Drop attacks stem from diverse mechanisms, including orthopedic causes (for example, leg weakness and knee instability), hemodynamic causes (for example, transient vertebrobasilar insuf ...
can be, among many others, an atonic seizure An atonic seizure (also called drop seizure, akinetic seizure, astatic seizure, or drop attack) is a type of seizure that consists of partial or complete loss of muscle tone that is caused by temporary alterations in brain function. These seizures ...
.[
Children may have behaviors that are easily mistaken for epileptic seizures but are not. These include ]breath-holding spell
Breath-holding spells (BHS) are the occurrence of episodic apnea in children, possibly associated with loss of consciousness, and changes in postural tone.
Breath-holding spells occur in approximately 5% of the population with equal distribution b ...
s, bedwetting, night terror
Night terror, also called sleep terror, is a sleep disorder causing feelings of panic or dread and typically occurring during the first hours of stage 3–4 non-rapid eye movement (NREM) sleep and lasting for 1 to 10 minutes. It can last long ...
s, tic
A tic is a sudden, repetitive, nonrhythmic motor movement or vocalization involving discrete muscle groups.American Psychiatric Association (2000)DSM-IV-TR: Tourette's Disorder.''Diagnostic and Statistical Manual of Mental Disorders'', 4th ed., ...
s and shudder attacks.[ ]Gastroesophageal reflux
Gastroesophageal reflux disease (GERD) or gastro-oesophageal reflux disease (GORD) is one of the upper gastrointestinal chronic diseases where stomach content persistently and regularly flows up into the esophagus, resulting in symptoms and/ ...
may cause arching of the back and twisting of the head to the side in infants, which may be mistaken for tonic-clonic seizures.
Misdiagnosis is frequent (occurring in about 5 to 30% of cases). Different studies showed that in many cases seizure-like attacks in apparent treatment-resistant epilepsy have a cardiovascular cause.[ Approximately 20% of the people seen at epilepsy clinics have PNES][ and of those who have PNES about 10% also have epilepsy;] separating the two based on the seizure episode alone without further testing is often difficult.[
]
Prevention
While many cases are not preventable, efforts to reduce head injuries, provide good care around the time of birth, and reduce environmental parasites such as the pork tapeworm
''Taenia solium'', the pork tapeworm, belongs to the cyclophyllid cestode family Taeniidae. It is found throughout the world and is most common in countries where pork is eaten. It is a tapeworm that uses humans as its definitive host and pigs ...
may be effective.[ Efforts in one part of Central America to decrease rates of pork tapeworm resulted in a 50% decrease in new cases of epilepsy.][
]
Complication
Epilepsy can be dangerous when seizure occurs at certain times. The possibility of drowning and having car accident is higher. It is also dangerous when seizure occurs during pregnancy. Certain anti-epileptic medications increase the risk of birth defects. It is also found that people with epilepsy are more likely to have psychological problems. Other complications include aspiration pneumonia and difficulty learning.
Management
Epilepsy is usually treated with daily 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 ...
once a second seizure has occurred, while medication may be started after the first seizure in those at high risk for subsequent seizures. Supporting people's self management of their condition may be useful. In drug-resistant cases different management options may be looked at including a special diet, the implantation of a neurostimulator, or neurosurgery
Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the medical specialty concerned with the surgical treatment of disorders which affect any portion of the nervous system including the brain, spinal cord and pe ...
.
First aid
Rolling people with an active tonic-clonic seizure onto their side and into the recovery position helps prevent fluids from getting into the lungs. Putting fingers, a bite block or tongue depressor in the mouth is not recommended as it might make the person vomit
Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose.
Vomiting can be the result of ailments like food poisoning, gastroenterit ...
or result in the rescuer being bitten.[ Efforts should be taken to prevent further self-injury.] Spinal precautions are generally not needed.[
If a seizure lasts longer than 5 minutes or if there are more than two seizures in an hour without a return to a normal level of consciousness between them, it is considered a ]medical emergency
A medical emergency is an acute injury or illness that poses an immediate risk to a person's life or long-term health, sometimes referred to as a situation risking "life or limb". These emergencies may require assistance from another, qualified ...
known as status epilepticus. This may require medical help to keep the airway open and protected; a nasopharyngeal airway
In medicine, a nasopharyngeal airway, also known as an NPA, nasal trumpet (because of its flared end), or nose hose, is a type of ''airway adjunct'', a tube that is designed to be inserted through the nasal passage down into the posterior pharynx ...
may be useful for this.[ At home the recommended initial medication for seizure of a long duration is ]midazolam
Midazolam, sold under the brand name Versed among others, is a benzodiazepine medication used for anesthesia and procedural sedation, and to treat severe agitation. It works by inducing sleepiness, decreasing anxiety, and causing a loss of ...
placed in the mouth. Diazepam
Diazepam, first marketed as Valium, is a medicine of the benzodiazepine family that acts as an anxiolytic. It is commonly used to treat a range of conditions, including anxiety, seizures, alcohol withdrawal syndrome, muscle spasms, insomnia, ...
may also be used rectally
The rectum is the final straight portion of the large intestine in humans and some other mammals, and the gut in others. The adult human rectum is about long, and begins at the rectosigmoid junction (the end of the sigmoid colon) at the le ...
. In hospital, intravenous lorazepam
Lorazepam, sold under the brand name Ativan among others, is a benzodiazepine medication. It is used to treat anxiety disorders, trouble sleeping, severe agitation, active seizures including status epilepticus, alcohol withdrawal, and c ...
is preferred. If two doses of benzodiazepines are not effective, other medications such as phenytoin
Phenytoin (PHT), sold under the brand name Dilantin among others, is an anti-seizure medication. It is useful for the prevention of tonic-clonic seizures (also known as grand mal seizures) and focal seizures, but not absence seizures. The in ...
are recommended. Convulsive status epilepticus that does not respond to initial treatment typically requires admission to the intensive care unit
220px, Intensive care unit
An intensive care unit (ICU), also known as an intensive therapy unit or intensive treatment unit (ITU) or critical care unit (CCU), is a special department of a hospital or health care facility that provides intensi ...
and treatment with stronger agents such as thiopentone
Sodium thiopental, also known as Sodium Pentothal (a trademark of Abbott Laboratories), thiopental, thiopentone, or Trapanal (also a trademark), is a rapid-onset short-acting barbiturate general anesthetic. It is the thiobarbiturate analog of p ...
or propofol.
Medications
The mainstay treatment of epilepsy is anticonvulsant medications, possibly for the person's entire life. The choice of anticonvulsant is based on seizure type, epilepsy syndrome, other medications used, other health problems, and the person's age and lifestyle. A single medication is recommended initially; if this is not effective, switching to a single other medication is recommended. Two medications at once is recommended only if a single medication does not work. In about half, the first agent is effective; a second single agent helps in about 13% and a third or two agents at the same time may help an additional 4%. About 30% of people continue to have seizures despite anticonvulsant treatment.[
There are a number of medications available including ]phenytoin
Phenytoin (PHT), sold under the brand name Dilantin among others, is an anti-seizure medication. It is useful for the prevention of tonic-clonic seizures (also known as grand mal seizures) and focal seizures, but not absence seizures. The in ...
, carbamazepine
Carbamazepine (CBZ), sold under the trade name Tegretol among others, is an anticonvulsant medication used primarily in the treatment of epilepsy and neuropathic pain. It is used as an adjunctive treatment in schizophrenia along with other m ...
and valproate
Valproate (VPA) and its valproic acid, sodium valproate, and valproate semisodium forms are medications primarily used to treat epilepsy and bipolar disorder and prevent migraine headaches. They are useful for the prevention of seizures in those ...
. Evidence suggests that phenytoin, carbamazepine, and valproate may be equally effective in both focal and generalized seizures. Controlled release
Modified-release dosage is a mechanism that (in contrast to immediate-release dosage) delivers a drug with a delay after its administration (delayed-release dosage) or for a prolonged period of time (extended-release R, XR, XLdosage) or to a sp ...
carbamazepine appears to work as well as immediate release carbamazepine, and may have fewer 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. Recently, ''Nux vomica'' and ''Cicuta virosa'' have been shown to produce significant anti-epileptic effects and no side effects. This could prove to be very helpful for a large segment of population. In the United Kingdom, carbamazepine or lamotrigine are recommended as first-line treatment for focal seizures, with levetiracetam
Levetiracetam, sold under the brand name Keppra among others, is a medication used to treat epilepsy. It is used for partial-onset, myoclonic, or tonic–clonic seizures and is taken either by mouth as an immediate or extended release formu ...
and valproate as second-line due to issues of cost and side effects. Valproate is recommended first-line for generalized seizures with lamotrigine being second-line. In those with absence seizures, ethosuximide
Ethosuximide, sold under the brand name Zarontin among others, is a medication used to treat absence seizures. It may be used by itself or with other antiseizure medications such as valproic acid. Ethosuximide is taken by mouth.
Ethosuximide i ...
or valproate are recommended; valproate is particularly effective in myoclonic seizures and tonic or atonic seizures. If seizures are well-controlled on a particular treatment, it is not usually necessary to routinely check the medication levels in the blood.
The least expensive anticonvulsant is phenobarbital
Phenobarbital, also known as phenobarbitone or phenobarb, sold under the brand name Luminal among others, is a medication of the barbiturate type. It is recommended by the World Health Organization (WHO) for the treatment of certain types of ep ...
at around US$5 a year.[ The ]World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of ...
gives it a first-line recommendation in the developing world and it is commonly used there. Access however may be difficult as some countries label it as a controlled drug
The prohibition of drugs through sumptuary law, sumptuary legislation or religious law is a common means of attempting to prevent the Recreational drug use, recreational use of certain intoxicating substances.
While some drugs are illegal to p ...
.[
Adverse effects from medications are reported in 10 to 90% of people, depending on how and from whom the data is collected.][ Most adverse effects are dose-related and mild.][ Some examples include mood changes, sleepiness, or an unsteadiness in gait.][ Certain medications have side effects that are not related to dose such as rashes, liver toxicity, or suppression of the bone marrow.][ Up to a quarter of people stop treatment due to adverse effects.][ Some medications are associated with ]birth defect
A birth defect, also known as a congenital disorder, is an abnormal condition that is present at birth regardless of its cause. Birth defects may result in disabilities that may be physical, intellectual, or developmental. The disabilities ca ...
s when used in pregnancy. Many of the common used medications, such as valproate, phenytoin, carbamazepine, phenobarbital, and gabapentin have been reported to cause increased risk of birth defects, especially when used during the first trimester
Pregnancy is the time during which one or more offspring develops ( gestates) inside a woman's uterus (womb). A multiple pregnancy involves more than one offspring, such as with twins.
Pregnancy usually occurs by sexual intercourse, but ...
.[ Despite this, treatment is often continued once effective, because the risk of untreated epilepsy is believed to be greater than the risk of the medications.] Among the antiepileptic medications, levetiracetam and lamotrigine seem to carry the lowest risk of causing birth defects.[
Slowly stopping medications may be reasonable in some people who do not have a seizure for two to four years; however, around a third of people have a recurrence, most often during the first six months.] Stopping is possible in about 70% of children and 60% of adults.[ Measuring medication levels is not generally needed in those whose seizures are well controlled.]
Surgery
Epilepsy surgery
Epilepsy surgery involves a neurosurgical procedure where an area of the brain involved in seizures is either resected, ablated, disconnected or stimulated. The goal is to eliminate seizures or significantly reduce seizure burden. Approximatel ...
may be an option for people with focal seizures that remain a problem despite other treatments. These other treatments include at least a trial of two or three medications.[ The goal of surgery is total control of seizures] and this may be achieved in 60–70% of cases. Common procedures include cutting out the hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, ...
via an anterior temporal lobe resection, removal of tumors, and removing parts of the neocortex.[ Some procedures such as a ]corpus callosotomy
Corpus callosotomy is a palliative surgical procedure for the treatment of medically refractory epilepsy. In this procedure the corpus callosum is cut through in an effort to limit the spread of epileptic activity between the two halves of the ...
are attempted in an effort to decrease the number of seizures rather than cure the condition.[ Following surgery, medications may be slowly withdrawn in many cases.][
]
Neurostimulation
Neurostimulation
Neurostimulation is the purposeful modulation of the nervous system's activity using invasive (e.g. microelectrodes) or non-invasive means (e.g. transcranial magnetic stimulation or transcranial electric stimulation, tES, such as tDCS or trans ...
via neuro-cybernetic prosthesis implantation, may be another option in those who are not candidates for surgery, providing chronic, pulsatile electrical stimulation of specific nerve or brain regions, alongside standard care. Three types have been used in those who do not respond to medications: vagus nerve stimulation (VNS), anterior thalamic stimulation, and closed-loop responsive stimulation.
Vagus nerve stimulation
Non-pharmacological modulation of neurotransmitters via high-level VNS (h-VNS) may reduce seizure frequency in children and adults who do not respond to medical and/or surgical therapy, when compared with low-level VNS (l-VNS). In a 2022 Cochrane review of 4 randomised controlled trials, with moderate certainty of evidence, people receiving h-VNS treatment were 73% more likely (13% more likely to 164% more likely) to experience a reduction in seizure frequency by at least 50% (the minimum threshold defined for individual clinical response). Potentially 249 (163 to 380) per 1000 people with drug-resistant epilepsy may achieve a 50% reduction in seizures following h-VNS, benefiting an additional 105 per 1000 people compared with l-VNS.
This outcome was limited by the number of studies available, and the quality of one trial in particular, wherein 3 people received l-VNS in error. A sensitivity analysis
Sensitivity analysis is the study of how the uncertainty in the output of a mathematical model or system (numerical or otherwise) can be divided and allocated to different sources of uncertainty in its inputs. A related practice is uncertainty anal ...
suggested that the best case scenario was that the likelihood of clinical response to h-VNS may be 91% (27% to 189%) higher than those receiving l-VNS. In the worst-case scenario, the likelihood of clinical response to h-VNS was still 61% higher (7% higher to 143% higher) than l-VNS.
Despite the potential benefit for h-VNS treatment, the Cochrane review also found that the risk of several adverse-effects was greater than those receiving l-VNS. There was moderate certainty of evidence that voice alteration or hoarseness risk may be 2.17(1.49 to 3.17) fold higher than people receiving l-VNS. Dyspnoea
Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing dis ...
risk was also 2.45 (1.07 to 5.60) times that of l-VNS receipients, although the low number of events and studies meant that the certainty of evidence was low. The risk of rebound-withdrawal symptoms, coughing, pain and paraesthesia was unclear.
Diet
There is promising evidence that a ketogenic diet
The ketogenic diet is a high- fat, adequate-protein, low-carbohydrate dietary therapy that in conventional medicine is used mainly to treat hard-to-control (refractory) epilepsy in children. The diet forces the body to burn fats rather than ca ...
(high-fat
In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food.
The term often refers specifically to triglycerides (triple est ...
, low-carbohydrate, adequate-protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...
) decreases the number of seizures and eliminates seizures in some; however, further research is necessary. It is a reasonable option in those who have epilepsy that is not improved with medications and for whom surgery is not an option. About 10% stay on the diet for a few years due to issues of effectiveness and tolerability. Side effects include stomach and intestinal problems in 30%, and there are long-term concerns about heart disease. Less radical diets are easier to tolerate and may be effective. It is unclear why this diet works. In people with coeliac disease or non-celiac gluten sensitivity and occipital calcifications, a gluten-free diet
A gluten-free diet (GFD) is a nutritional plan that strictly excludes gluten, which is a mixture of proteins found in wheat (and all of its species and hybrids, such as spelt, kamut, and triticale), as well as barley, rye, and oats. The incl ...
may decrease the frequency of seizures.
Other
Avoidance therapy consists of minimizing or eliminating triggers. For example, those who are sensitive to light may have success with using a small television, avoiding video games, or wearing dark glasses. Operant-based biofeedback
The professional practice of behavior analysis is a domain of behavior analysis, the others being radical behaviorism, experimental analysis of behavior and applied behavior analysis. The practice of behavior analysis is the delivery of interven ...
based on the EEG waves has some support in those who do not respond to medications. Psychological methods should not, however, be used to replace medications.
Exercise has been proposed as possibly useful for preventing seizures, with some data to support this claim. Some dogs, commonly referred to as seizure dogs, may help during or after a seizure. It is not clear if dogs have the ability to predict seizures before they occur.
There is moderate-quality evidence supporting the use of psychological interventions along with other treatments in epilepsy. This can improve quality of life, enhance emotional wellbeing, and reduce fatigue in adults and adolescents. Psychological interventions may also improve seizure control for some individuals by promoting self-management and adherence.
As an add-on therapy in those who are not well controlled with other medications, cannabidiol
Cannabidiol (CBD) is a phytocannabinoid discovered in 1940. It is one of 113 identified cannabinoids in cannabis plants, along with tetrahydrocannabinol (THC), and accounts for up to 40% of the plant's extract. , clinical research on CBD in ...
appears to be useful in some children. In 2018 the FDA approved this product for Lennox–Gastaut syndrome
Lennox–Gastaut syndrome (LGS) is a complex, rare, and severe childhood-onset epilepsy. It is characterized by multiple and concurrent seizure types, cognitive dysfunction, and slow spike waves on electroencephalogram (EEG). Typically, it presents ...
and Dravet syndrome
Dravet syndrome, previously known as severe myoclonic epilepsy of infancy (SMEI), is an autosomal dominant genetic disorder which causes a catastrophic form of epilepsy, with prolonged seizures that are often triggered by hot temperatures or feve ...
.
There are a few studies on the use of dexamethasone for the successful treatment of drug-resistant seizures in both adults and children
In pregnancy
In women of childbearing age, use of antiepileptic drugs is a major concern balancing possible side effects on the fetus against risk from uncontrolled seizures. Use of AEDs entail teratogenic effects including intrauterine growth retardation, major congenital malformations and developmental (neurocognitive) and behavioral issues, that need to be discussed with the patient at the time of starting the AEDs and before they plan pregnancy. Most women with epilepsy receive safe and effective treatment and have normal children, however risks exist. The International League Against Epilepsy created a task force on women and epilepsy which published consensus recommendations to guide therapy decisions until more definitive evidence is available in the future.
Alternative medicine
Alternative medicine, including acupuncture
Acupuncture is a form of alternative medicine and a component of traditional Chinese medicine (TCM) in which thin needles are inserted into the body. Acupuncture is a pseudoscience; the theories and practices of TCM are not based on scientif ...
, routine vitamins
A vitamin is an organic molecule (or a set of molecules closely related chemically, i.e. vitamers) that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism. Essential nutrien ...
, and yoga
Yoga (; sa, योग, lit=yoke' or 'union ) is a group of physical, mental, and spiritual practices or disciplines which originated in ancient India and aim to control (yoke) and still the mind, recognizing a detached witness-consci ...
, have no reliable evidence to support their use in epilepsy. Melatonin, , is insufficiently supported by evidence. The trials were of poor methodological quality and it was not possible to draw any definitive conclusions.
Several supplements (with varied reliabilities of evidence) have been reported to be helpful for drug-resistant epilepsy. These include high-dose Omega-3, berberine, Manuka honey, Reishi and Lion's Mane mushrooms, curcumin, vitamin E, coenzyme Q-10, and resveratrol. The reason these can work(in theory) is that they reduce inflammation or oxidative stress, two of the major mechanism contributing to epilepsy.
Prognosis
Epilepsy cannot usually be cured, but medication can control seizures effectively in about 70% of cases.[ Of those with generalized seizures, more than 80% can be well controlled with medications while this is true in only 50% of people with focal seizures.][ One predictor of long-term outcome is the number of seizures that occur in the first six months.] Other factors increasing the risk of a poor outcome include little response to the initial treatment, generalized seizures, a family history of epilepsy, psychiatric problems, and waves on the EEG representing generalized epileptiform activity. In the developing world, 75% of people are either untreated or not appropriately treated.[ In Africa, 90% do not get treatment.][ This is partly related to appropriate medications not being available or being too expensive.][
]
Mortality
People with epilepsy are at an increased risk of death.[ This increase is between 1.6 and 4.1 fold greater than that of the general population.] The greatest increase in mortality from epilepsy is among the elderly.[ Those with epilepsy due to an unknown cause have little increased risk.][
Mortality is often related to: the underlying cause of the seizures, status epilepticus, suicide, ]trauma
Trauma most often refers to:
* Major trauma, in physical medicine, severe physical injury caused by an external source
* Psychological trauma, a type of damage to the psyche that occurs as a result of a severely distressing event
*Traumatic i ...
, and sudden unexpected death in epilepsy
Sudden unexpected death in epilepsy (SUDEP) is a fatal complication of epilepsy. It is defined as the sudden and unexpected, non-traumatic and non-drowning death of a person with epilepsy, without a toxicological or anatomical cause of death det ...
(SUDEP). Death from status epilepticus is primarily due to an underlying problem rather than missing doses of medications.[ The risk of suicide is between 2 and 6 times higher in those with epilepsy;] the cause of this is unclear.[ SUDEP appears to be partly related to the frequency of generalized tonic-clonic seizures] and accounts for about 15% of epilepsy-related deaths;[ it is unclear how to decrease its risk.][
In the United Kingdom, it is estimated that 40–60% of deaths are possibly preventable.] In the developing world, many deaths are due to untreated epilepsy leading to falls or status epilepticus.[
]
Epidemiology
Epilepsy is one of the most common serious neurological disorders affecting about 39 million people . It affects 1% of the population by age 20 and 3% of the population by age 75.[ It is more common in males than females with the overall difference being small.][ Most of those with the disorder (80%) are in low income populations or the developing world.][
The estimated prevalence of active epilepsy () is in the range 3–10 per 1,000, with active epilepsy defined as someone with epilepsy who has had a least one unprovoked seizure in the last five years.][ Epilepsy begins each year in 40–70 per 100,000 in developed countries and 80–140 per 100,000 in developing countries.][ Poverty is a risk and includes both being from a poor country and being poor relative to others within one's country.][ In the developed world epilepsy most commonly starts either in the young or in the old.][ In the developing world its onset is more common in older children and young adults due to the higher rates of trauma and infectious diseases.][ In developed countries the number of cases a year has decreased in children and increased among the elderly between the 1970s and 2003.] This has been attributed partly to better survival following strokes in the elderly.[
]
History
The oldest medical records show that epilepsy has been affecting people at least since the beginning of recorded history. Throughout ancient history
Ancient history is a time period from the beginning of writing and recorded human history to as far as late antiquity. The span of recorded history is roughly 5,000 years, beginning with the Sumerian cuneiform script. Ancient history cove ...
, the disease was thought to be a spiritual condition.[ The world's oldest description of an epileptic seizure comes from a text in ]Akkadian Akkadian or Accadian may refer to:
* Akkadians, inhabitants of the Akkadian Empire
* Akkadian language, an extinct Eastern Semitic language
* Akkadian literature, literature in this language
* Akkadian cuneiform
Cuneiform is a logo- syllabi ...
(a language used in ancient Mesopotamia
Mesopotamia ''Mesopotamíā''; ar, بِلَاد ٱلرَّافِدَيْن or ; syc, ܐܪܡ ܢܗܪ̈ܝܢ, or , ) is a historical region of Western Asia situated within the Tigris–Euphrates river system, in the northern part of the ...
) and was written around 2000 BC.[ The person described in the text was diagnosed as being under the influence of a moon god, and underwent an ]exorcism
Exorcism () is the religious or spiritual practice of evicting demons, jinns, or other malevolent spiritual entities from a person, or an area, that is believed to be possessed. Depending on the spiritual beliefs of the exorcist, this may be ...
.[ Epileptic seizures are listed in the Code of Hammurabi () as reason for which a purchased slave may be returned for a refund,][ and the Edwin Smith Papyrus () describes cases of individuals with epileptic convulsions.][
The oldest known detailed record of the disease itself is in the '' Sakikku'', a Babylonian ]cuneiform
Cuneiform is a logo-syllabic script that was used to write several languages of the Ancient Middle East. The script was in active use from the early Bronze Age until the beginning of the Common Era. It is named for the characteristic wedge-sh ...
medical text from 10671046 BC.[ This text gives signs and symptoms, details treatment and likely outcomes,][ and describes many features of the different seizure types.][ As the Babylonians had no biomedical understanding of the nature of disease, they attributed the seizures to possession by evil spirits and called for treating the condition through spiritual means.][ Around 900 BC, ]Punarvasu Atreya
Punarvasu is a Nakshatra in Hindu astrology, which refers to the two brightest stars in the constellation of Gemini: Castor and Pollux.
Astrology
Punarvasu extends from 20 degrees 00 minutes of Mithun (Gemini) to 03 degrees 20 minutes of Kar ...
described epilepsy as loss of consciousness; this definition was carried forward into the Ayurvedic text of Charaka Samhita (about 400 BC).
The ancient Greeks
Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity ( AD 600), that comprised a loose collection of cult ...
had contradictory views of the disease. They thought of epilepsy as a form of spiritual possession, but also associated the condition with genius and the divine. One of the names they gave to it was the ''sacred disease'' (ἠ ἱερὰ νόσος). Epilepsy appears within Greek mythology: it is associated with the Moon goddesses Selene
In ancient Greek mythology and religion, Selene (; grc-gre, Σελήνη , meaning "Moon"''A Greek–English Lexicon's.v. σελήνη) is the goddess and the personification of the Moon. Also known as Mene, she is traditionally the daughter of ...
and Artemis
In ancient Greek mythology and religion, Artemis (; grc-gre, Ἄρτεμις) is the goddess of the hunt, the wilderness, wild animals, nature, vegetation, childbirth, care of children, and chastity. She was heavily identified wit ...
, who afflicted those who upset them. The Greeks thought that important figures such as Julius Caesar
Gaius Julius Caesar (; ; 12 July 100 BC – 15 March 44 BC), was a Roman general and statesman. A member of the First Triumvirate, Caesar led the Roman armies in the Gallic Wars before defeating his political rival Pompey in a civil war, ...
and Hercules
Hercules (, ) is the Roman equivalent of the Greek divine hero Heracles, son of Jupiter and the mortal Alcmena. In classical mythology, Hercules is famous for his strength and for his numerous far-ranging adventures.
The Romans adapted the ...
had the disease.[ The notable exception to this divine and spiritual view was that of the school of ]Hippocrates
Hippocrates of Kos (; grc-gre, Ἱπποκράτης ὁ Κῷος, Hippokrátēs ho Kôios; ), also known as Hippocrates II, was a Greek physician of the classical period who is considered one of the most outstanding figures in the history o ...
. In the fifth century BC, Hippocrates rejected the idea that the disease was caused by spirits. In his landmark work ''On the Sacred Disease
''On the Sacred Disease'' is a work of the Hippocratic Corpus, written about 400 B.C. Its authorship cannot be confirmed, so is regarded as dubious. The treatise is thought to contain one of the first recorded observations of epilepsy in humans. ...
'', he proposed that epilepsy was not divine in origin and instead was a medically treatable problem originating in the brain. He accused those of attributing a sacred cause to the disease of spreading ignorance through a belief in superstitious magic.[ Hippocrates proposed that heredity was important as a cause, described worse outcomes if the disease presents at an early age, and made note of the physical characteristics as well as the social shame associated with it.][ Instead of referring to it as the ''sacred disease'', he used the term ''great disease'', giving rise to the modern term ''grand mal'', used for tonic–clonic seizures.][ Despite his work detailing the physical origins of the disease, his view was not accepted at the time.] Evil spirits continued to be blamed until at least the 17th century.
In Ancient Rome
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC ...
people did not eat or drink with the same pottery as that used by someone who was affected. People of the time would spit on their chest believing that this would keep the problem from affecting them.[ According to ]Apuleius
Apuleius (; also called Lucius Apuleius Madaurensis; c. 124 – after 170) was a Numidian Latin-language prose writer, Platonist philosopher and rhetorician. He lived in the Roman province of Numidia, in the Berber city of Madauros, modern- ...
and other ancient physicians, in order to detect epilepsy, it was common to light a piece of ''gagates'', whose smoke would trigger the seizure. Occasionally a spinning potter's wheel
In pottery, a potter's wheel is a machine used in the shaping (known as throwing) of clay into round ceramic ware. The wheel may also be used during the process of trimming excess clay from leather-hard dried ware that is stiff but malleable, a ...
was used, perhaps a reference to photosensitive epilepsy
Photosensitive epilepsy (PSE) is a form of epilepsy in which seizures are triggered by visual stimuli that form patterns in time or space, such as flashing lights; bold, regular patterns; or regular moving patterns.
PSE affects approximately o ...
.
In most cultures, persons with epilepsy have been stigmatized, shunned, or even imprisoned. As late as in the second half of the 20th century, in Tanzania
Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands ...
and other parts of Africa epilepsy was associated with possession by evil spirits, witchcraft, or poisoning and was believed by many to be contagious. In the Salpêtrière, the birthplace of modern neurology, Jean-Martin Charcot found people with epilepsy side by side with the mentally ill, those with chronic syphilis, and the criminally insane. In ancient Rome
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC ...
, epilepsy was known as the ''morbus comitialis'' ('disease of the assembly hall') and was seen as a curse from the gods. In northern Italy, epilepsy was once traditionally known as Saint Valentine's malady. In at least the 1840s in the United States of America
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territo ...
, epilepsy was known as the ''falling sickness'' or ''the falling fits'', and was considered a form of medical insanity
Insanity, madness, lunacy, and craziness are behaviors performed by certain abnormal mental or behavioral patterns. Insanity can be manifest as violations of societal norms, including a person or persons becoming a danger to themselves or t ...
. Around the same time period, epilepsy was known in France as the ''haut-mal'' ('high evil'), ''mal-de terre'' ('earthen sickness'), ''mal de Saint Jean'' (' Saint John's sickness'), ''mal des enfans'' ('child sickness'), and ''mal-caduc'' ('obsolete sickness'). Patients of epilepsy in France were also known as ''tombeurs'', or 'people who fall', due to the seizures and loss of consciousness in an epileptic episode.
In the mid-19th century, the first effective anti-seizure medication, bromide
A bromide ion is the negatively charged form (Br−) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant ...
, was introduced. The first modern treatment, phenobarbital
Phenobarbital, also known as phenobarbitone or phenobarb, sold under the brand name Luminal among others, is a medication of the barbiturate type. It is recommended by the World Health Organization (WHO) for the treatment of certain types of ep ...
, was developed in 1912, with phenytoin coming into use in 1938.
Society and culture
Stigma
Stigma is commonly experienced, around the world, by those with epilepsy. It can affect people economically, socially and culturally.[ In India and China, epilepsy may be used as justification to deny marriage.][ People in some areas still believe those with epilepsy to be ]curse
A curse (also called an imprecation, malediction, execration, malison, anathema, or commination) is any expressed wish that some form of adversity or misfortune will befall or attach to one or more persons, a place, or an object. In particula ...
d.[ In parts of Africa, such as ]Tanzania
Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands ...
and Uganda
}), is a landlocked country in East Africa. The country is bordered to the east by Kenya, to the north by South Sudan, to the west by the Democratic Republic of the Congo, to the south-west by Rwanda, and to the south by Tanzania. The sou ...
, epilepsy is claimed to be associated with possession by evil spirits, witchcraft, or poisoning and is incorrectly believed by many to be contagious
Contagious may refer to:
* Contagious disease
Literature
* Contagious (magazine), a marketing publication
* ''Contagious'' (novel), a science fiction thriller novel by Scott Sigler
Music
Albums
*''Contagious'' (Peggy Scott-Adams album), 1997
* ...
.[ Before 1971 in the United Kingdom, epilepsy was considered grounds for the annulment of marriage.][ The stigma may result in some people with epilepsy denying that they have ever had seizures.]
Economics
Seizures result in direct economic costs of about one billion dollars in the United States.[ Epilepsy resulted in economic costs in Europe of around 15.5 billion euros in 2004.] In India epilepsy is estimated to result in costs of US$1.7 billion or 0.5% of the GDP.[ It is the cause of about 1% of emergency department visits (2% for emergency departments for children) in the United States.]
Vehicles
Those with epilepsy are at about twice the risk of being involved in a motor vehicular collision and thus in many areas of the world are not allowed to drive or only able to drive if certain conditions are met.[ Diagnostic delay has been suggested to be a cause of some potentially avoidable motor vehicle collisions since at least one study showed that most motor vehicle accidents occurred in those with undiagnosed nonmotor seizures as opposed to those with motor seizures at epilepsy onset. In some places physicians are required by law to report if a person has had a seizure to the licensing body while in others the requirement is only that they encourage the person in question to report it himself.][ Countries that require physician reporting include Sweden, Austria, Denmark and Spain.][ Countries that require the individual to report include the UK and New Zealand, and physicians may report if they believe the individual has not already.][ In Canada, the United States and Australia the requirements around reporting vary by province or state.][ If seizures are well controlled most feel allowing driving is reasonable.][ The amount of time a person must be free from seizures before he can drive varies by country.][ Many countries require one to three years without seizures.][ In the United States the time needed without a seizure is determined by each state and is between three months and one year.]
Those with epilepsy or seizures are typically denied a pilot license. In Canada if an individual has had no more than one seizure, they may be considered after five years for a limited license if all other testing is normal. Those with febrile seizures and drug related seizures may also be considered.[ In the United States, the ]Federal Aviation Administration
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...
does not allow those with epilepsy to get a commercial pilot license. Rarely, exceptions can be made for persons who have had an isolated seizure or febrile seizures and have remained free of seizures into adulthood without medication. In the United Kingdom, a full national private pilot license requires the same standards as a professional driver's license. This requires a period of ten years without seizures while off medications. Those who do not meet this requirement may acquire a restricted license if free from seizures for five years.[
]
Support organizations
There are organizations that provide support for people and families affected by epilepsy. The ''Out of the Shadows'' campaign, a joint effort by the World Health Organization, the International League Against Epilepsy The International League Against Epilepsy was started in 1909. Its goal is to improve the lives of people with epilepsy through research.
They run the medical journals ''Epilepsia'', ''Epilepsia Open'', and ''Epileptic Disorders
''Epileptic Disor ...
and the International Bureau for Epilepsy, provides help internationally.[ In the United States, the ]Epilepsy Foundation
The Epilepsy Foundation, also Epilepsy Foundation of America (EFA), is a non-profit national foundation, headquartered in Bowie, Maryland, dedicated to the welfare of people with epilepsy and seizure disorders. The foundation was established in 196 ...
is a national organization that works to increase the acceptance of those with the disorder, their ability to function in society and to promote research for a cure. The Epilepsy Foundation, some hospitals, and some individuals also run support groups in the United States. In Australia, the Epilepsy Foundation
The Epilepsy Foundation, also Epilepsy Foundation of America (EFA), is a non-profit national foundation, headquartered in Bowie, Maryland, dedicated to the welfare of people with epilepsy and seizure disorders. The foundation was established in 196 ...
provides support, delivers education and training and funds research for people living with epilepsy.
International Epilepsy Day (World Epilepsy Day) began in 2015 and occurs on the second Monday in February.
Purple Day, a different world-wide epilepsy awareness day for epilepsy, was initiated by a nine-year-old Canadian named Cassidy Megan in 2008, and is every year on March 26.
Research
Seizure prediction and modeling
Seizure prediction refers to attempts to forecast epileptic seizures based on the EEG before they occur. , no effective mechanism to predict seizures has been developed. Kindling
Kindling is material for firelighting
Kindling may also refer to:
* ''Kindling'' (album), a 1973 album by Gene Parsons
* ''Kindling'' (film), a 1915 film by Cecil B. DeMille
* ''Kindling'' (Mick Farren novel)
* ''Ruined City'' (novel) or ''Ki ...
, where repeated exposures to events that could cause seizures eventually causes seizures more easily, has been used to create animal model
An animal model (short for animal disease model) is a living, non-human, often genetic-engineered animal used during the research and investigation of human disease, for the purpose of better understanding the disease process without the risk of ha ...
s of epilepsy. One of the hypotheses present in the literature is based on inflammatory pathways. Studies supporting this mechanism revealed that inflammatory, glycolipid, and oxidative factors are higher in epilepsy patients, especially those with generalized epilepsy.
Potential future therapies
Gene therapy
Gene therapy is a medical field which focuses on the genetic modification of cells to produce a therapeutic effect or the treatment of disease by repairing or reconstructing defective genetic material. The first attempt at modifying human DN ...
is being studied in some types of epilepsy. Medications that alter immune function, such as intravenous immunoglobulins, are poorly supported by evidence. Noninvasive stereotactic radiosurgery is, , being compared to standard surgery for certain types of epilepsy.
Other animals
Epilepsy occurs in a number of other animals including dogs and cats; it is in fact the most common brain disorder in dogs. It is typically treated with anticonvulsants such as phenobarbital or bromide
A bromide ion is the negatively charged form (Br−) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant ...
in dogs and phenobarbital
Phenobarbital, also known as phenobarbitone or phenobarb, sold under the brand name Luminal among others, is a medication of the barbiturate type. It is recommended by the World Health Organization (WHO) for the treatment of certain types of ep ...
in cats. Imepitoin
Imepitoin (), sold under the brand name Pexion, is an anticonvulsant which is used in veterinary medicine in Europe to treat epilepsy in dogs. It was recently approved in the United States. The drug also has anxiolytic effects. It was originally ...
is also used in dogs. While generalized seizures in horse
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million yea ...
s are fairly easy to diagnose, it may be more difficult in non-generalized seizures and EEG
Electroencephalography (EEG) is a method to record an electrogram of the spontaneous electrical activity of the brain. The biosignals detected by EEG have been shown to represent the postsynaptic potentials of pyramidal neurons in the neocortex ...
s may be useful.
References
Further reading
*
*
External links
*
World Health Organization fact sheet
*
*
{{Good article
Articles containing video clips
Disorders causing seizures
Neurological disorders in children
Wikipedia medicine articles ready to translate (full)
Wikipedia neurology articles ready to translate