Cyclizine, sold under a number of brand names, is a medication used to treat and prevent

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...

vomiting 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 Human nose, nose. Vomiting can be the result of ailments like Food-poisoning, foo ...

and

dizziness Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a common medical c ...

due to

motion sickness Motion sickness occurs due to a difference between actual and expected motion. Symptoms commonly include nausea, vomiting, cold sweat, headache, dizziness, tiredness, loss of appetite, and increased salivation. Complications may rarely include d ...

vertigo Vertigo is a condition where a person has the sensation of movement or of surrounding objects moving when they are not. Often it feels like a spinning or swaying movement. This may be associated with nausea, vomiting, sweating, or difficulties w ...

. It may also be used for nausea after

general anaesthesia General anaesthesia (UK) or general anesthesia (US) is a medically induced loss of consciousness that renders the patient unarousable even with painful stimuli. This effect is achieved by administering either intravenous or inhalational general ...

or that which developed from

opioid Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid us ...

use. It is taken

by mouth Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are i ...

, in the

rectum The rectum is the final straight portion of the large intestine in humans and some other mammals, and the Gastrointestinal tract, gut in others. The adult human rectum is about long, and begins at the rectosigmoid junction (the end of the s ...

, or injected into a vein. Common side effects include sleepiness, dry mouth,

constipation Constipation is a bowel dysfunction that makes bowel movements infrequent or hard to pass. The stool is often hard and dry. Other symptoms may include abdominal pain, bloating, and feeling as if one has not completely passed the bowel movement ...

, and trouble with vision. More serious side effects include

low blood pressure Hypotension is low blood pressure. Blood pressure is the force of blood pushing against the walls of the arteries as the heart pumps out blood. Blood pressure is indicated by two numbers, the systolic blood pressure (the top number) and the dia ...

and

urinary retention Urinary retention is an inability to completely empty the bladder. Onset can be sudden or gradual. When of sudden onset, symptoms include an inability to urinate and lower abdominal pain. When of gradual onset, symptoms may include loss of bladd ...

. It is not generally recommended in young children or those with

glaucoma Glaucoma is a group of eye diseases that result in damage to the optic nerve (or retina) and cause vision loss. The most common type is open-angle (wide angle, chronic simple) glaucoma, in which the drainage angle for fluid within the eye rem ...

. Cyclizine appears to be safe during

pregnancy 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 ca ...

but has not been well studied. It is in the

anticholinergic Anticholinergics (anticholinergic agents) are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system. These agents inhibit the parasympathetic nervous system ...

and

antihistamine Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ...

family of medications. Cyclizine was discovered in 1947. It is on the

World Health Organization's List of Essential Medicines The WHO Model List of Essential Medicines (aka Essential Medicines List or EML), published by the World Health Organization (WHO), contains the medications considered to be most effective and safe to meet the most important needs in a health ...

. In the United States it is available

over the counter Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a requirement for a prescription from a healthcare professional, as opposed to prescription drugs, which may be supplied only to consumers possessing a valid prescr ...

Medical uses

Primary uses include

and

associated with

and post-operatively following administration of

general anesthesia General anaesthesia (UK) or general anesthesia (US) is a medically induced loss of consciousness that renders the patient unarousable even with painful stimuli. This effect is achieved by administering either intravenous or inhalational general ...

and

s. It is sometimes given in

hyperemesis gravidarum Hyperemesis gravidarum (HG) is a pregnancy complication that is characterized by severe nausea, vomiting, weight loss, and possibly dehydration. Feeling faint may also occur. It is considered more severe than morning sickness. Symptoms often get ...

, although the manufacturer advises that it be avoided in pregnancy. Off-license use often occurs with specialists in hospitals to treat inpatients who have become severely dehydrated in pregnancy. An off-label use is as an opioid/opiate potentiator. The drug Diconal is a combination of cyclizine and the opioid

dipipanone Dipipanone (Pipadone) is a strong opioid analgesic drug, used for acute pain by mouth (PO) for adults - initially 10 mg every 6 hours, then increased if necessary up to 30 mg every 6 hours, with the dose to be increased gradually. It is often use ...

. Dipipanone is a

schedule I controlled substance This is the list of Schedule I drugs as defined by the United States Controlled Substances Act. 21 CFRbr>1308.11(CSA Sched I) with changes through (Oct 18, 2012). Retrieved September 6, 2013. The following findings are required for drugs to be pl ...

in the US.

Contraindications

Its antimuscarinic action warrants caution in patients with

prostatic hypertrophy Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss o ...

, urinary retention, or angle-closure

. Liver disease exacerbates its sedative effects.

Adverse effects

Common (over 10%) —

Drowsiness Somnolence (alternatively sleepiness or drowsiness) is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia). It has distinct meanings and causes. It can refer to the usual state preceding falling asleep ...

dry mouth Xerostomia, also known as dry mouth, is dryness in the mouth, which may be associated with a change in the composition of saliva, or reduced salivary flow, or have no identifiable cause. This symptom is very common and is often seen as a side eff ...

. Uncommon (1% to 10%) — Headache, psychomotor impairment, dermatitis, and

antimuscarinic A muscarinic receptor antagonist (MRA) is a type of anticholinergic agent that blocks the activity of the muscarinic acetylcholine receptor. The muscarinic receptor is a protein involved in the transmission of signals through certain parts of the ...

effects such as diplopia (double vision),

tachycardia Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal (su ...

and gastro-intestinal disturbances. Rare (less than 1%) — Hypersensitivity reactions (

bronchospasm Bronchospasm or a bronchial spasm is a sudden constriction of the muscles in the walls of the bronchioles. It is caused by the release (degranulation) of substances from mast cells or basophils under the influence of anaphylatoxins. It causes di ...

angioedema Angioedema is an area of swelling ( edema) of the lower layer of skin and tissue just under the skin or mucous membranes. The swelling may occur in the face, tongue, larynx, abdomen, or arms and legs. Often it is associated with hives, which ...

anaphylaxis Anaphylaxis is a serious, potentially fatal allergic reaction and medical emergency that is rapid in onset and requires immediate medical attention regardless of use of emergency medication on site. It typically causes more than one of the follow ...

, rashes and

photosensitivity Photosensitivity is the amount to which an object reacts upon receiving photons, especially visible light. In medicine, the term is principally used for abnormal reactions of the skin, and two types are distinguished, photoallergy and phototoxicity. ...

reactions), extrapyramidal effects, dizziness, confusion, depression, sleep disturbances,

tremor A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving oscillations or twitching movements of one or more body parts. It is the most common of all involuntary movements and can affect the hands, arms, eyes, fa ...

, liver dysfunction, and

hallucination A hallucination is a perception in the absence of an external stimulus that has the qualities of a real perception. Hallucinations are vivid, substantial, and are perceived to be located in external objective space. Hallucination is a combinatio ...

Pharmacology

Cyclizine is a

piperazine Piperazine () is an organic compound that consists of a six-membered ring containing two nitrogen atoms at opposite positions in the ring. Piperazine exists as small alkaline deliquescent crystals with a saline taste. The piperazines are a broad ...

derivative with histamine H₁-receptor antagonist (

) activity. The precise mechanism of action in inhibiting the symptoms of motion sickness is not well understood. It may have effects directly on the

vestibular system The vestibular system, in vertebrates, is a sensory system that creates the sense of balance and spatial orientation for the purpose of coordinating movement with balance. Together with the cochlea, a part of the auditory system, it constitutes ...

and on the

chemoreceptor trigger zone The chemoreceptor trigger zone (CTZ) is an area of the medulla oblongata that receives inputs from blood-borne drugs or hormones, and communicates with other structures in the vomiting center to initiate vomiting. The CTZ is located within the area ...

. Cyclizine exerts a central

(

) action.

Synthesis

Cyclizine may be prepared by the Eschweiler–Clarke methylation of

diphenylmethylpiperazine 1-(Diphenylmethyl)piperazine, also known as benzhydrylpiperazine, is a chemical compound and piperazine derivative. It features a piperazine ring with a benzhydryl (diphenyl methyl) group bound to one of the nitrogen Nitrogen is the chemical ...

or by reaction of benzhydryl bromide with

1-methylpiperazine ''N''-Methylpiperazine is a heterocyclic organic compound. Uses ''N''-Methylpiperazine is a common building block used in organic synthesis. For example, ''N''-methylpiperazine is used in the manufacture of various pharmaceutical drugs includin ...

in acetonitrile to form the hydrobromide salt of the drug.

History

Cyclizine was developed in the American division of pharmacy company

Burroughs Wellcome GSK plc, formerly GlaxoSmithKline plc, is a British multinational pharmaceutical and biotechnology company with global headquarters in London, England. Established in 2000 by a merger of Glaxo Wellcome and SmithKline Beecham. GSK is the tent ...

(today

GlaxoSmithKline GSK plc, formerly GlaxoSmithKline plc, is a British multinational pharmaceutical and biotechnology company with global headquarters in London, England. Established in 2000 by a merger of Glaxo Wellcome and SmithKline Beecham. GSK is the ten ...

) during a research study involving many drugs of the antihistamine group. Cyclizine was quickly clinically found as a potent and long-acting antiemetic. The company named the substance – or more precisely cyclizine's

hydrochloride In chemistry, a hydrochloride is an acid salt resulting, or regarded as resulting, from the reaction of hydrochloric acid with an organic base (e.g. an amine). An alternative name is chlorhydrate, which comes from French. An archaic alternative na ...

form which it usually appears in – "marezine hydrochloride" and started to sell it in the United States under trade name ''Marezine''. Selling was begun in

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

under trade name ''Marzine'' in 1965. The substance received more credit when

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

chose it as a space antiemetic for the first occupied moon flight. Cyclizine was introduced to many countries as a common antiemetic. It is an over-the-counter drug in many countries because it has been well tolerated, although it has not been studied much.

Society and culture

Some people using methadone recreationally combine cyclizine with their

methadone Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid dependence. It is used to treat chronic pain, and it is also used to treat addiction to heroin ...

dose, a combination that is known to produce strong

psychoactive A psychoactive drug, psychopharmaceutical, psychoactive agent or psychotropic drug is a chemical substance, that changes functions of the nervous system, and results in alterations in perception, mood, consciousness, cognition or behavior. Th ...

effects. It has also been used recreationally for its

effects to induce hallucinations. It has been used illegally in

greyhound racing Greyhound racing is an organized, competitive sport in which greyhounds are raced around a track. There are two forms of greyhound racing, track racing (normally around an oval track) and coursing; the latter is now banned in most countries. Tra ...

to sabotage a dog's performance.

Names

As cyclizine hydrochloride tablets and cyclizine lactate solution for intramuscular or intravenous injection (brand names: Valoid in UK and South Africa and Marezine, Marzine and Emoquil in US). Cyclizine was marketed as Bonine for Kids in the US, but was discontinued in 2012, and replaced with meclizine.

Cyclizine derivatives

References

External links

* {{portal bar, Medicine Antiemetics Cyclizines Diphenylmethylpiperazines H1 receptor antagonists Wikipedia medicine articles ready to translate World Health Organization essential medicines