Citalopram, sold under the brand name Celexa among others, is an

antidepressant Antidepressants are a class of medications used to treat major depressive disorder, anxiety disorders, chronic pain, and addiction. Common side effects of antidepressants include Xerostomia, dry mouth, weight gain, dizziness, headaches, akathi ...

of the

selective serotonin reuptake inhibitor Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs primarily work by blo ...

(SSRI) class. It is used to treat

major depressive disorder Major depressive disorder (MDD), also known as clinical depression, is a mental disorder characterized by at least two weeks of pervasive depression (mood), low mood, low self-esteem, and anhedonia, loss of interest or pleasure in normally ...

obsessive compulsive disorder Obsession may refer to: Psychology * Celebrity worship syndrome, obsessive addictive disorder to a celebrity's personal and professional life * Obsession (psychology), a persistent attachment to an object or idea * Fixation (psychology), persi ...

panic disorder Panic disorder is a mental disorder, specifically an anxiety disorder, characterized by reoccurring unexpected panic attacks. Panic attacks are sudden periods of intense fear that may include palpitations, sweating, shaking, shortness of breath ...

, and

social phobia Social anxiety disorder (SAD), also known as social phobia, is an anxiety disorder characterized by sentiments of fear and anxiety in social situations, causing considerable distress and impairing ability to function in at least some as ...

. The antidepressant effects may take one to four weeks to occur. It is typically taken orally (swallowed by mouth). In some European countries, it is sometimes given

intravenously Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutr ...

(injected into a vein) to initiate treatment, before switching to the oral route of administration for continuation of treatment. It has also been used intravenously in other parts of the world in some other circumstances. Common side effects include nausea, trouble sleeping, sexual problems, shakiness, feeling tired, and sweating. Serious side effects include an increased risk of

suicide Suicide is the act of intentionally causing one's own death. Risk factors for suicide include mental disorders, physical disorders, and substance abuse. Some suicides are impulsive acts driven by stress (such as from financial or ac ...

in those under the age of 25,

serotonin syndrome Serotonin syndrome (SS) is a group of symptoms that may occur with the use of certain Serotonin, serotonergic medications or Recreational drug use, drugs. The symptoms can range from mild to severe, and are potentially fatal. Symptoms in mild c ...

glaucoma Glaucoma is a group of eye diseases that can lead to damage of the optic nerve. The optic nerve transmits visual information from the eye to the brain. Glaucoma may cause vision loss if left untreated. It has been called the "silent thief of ...

, and QT prolongation. It should not be used in persons who take or have recently taken an MAO inhibitor. There are concerns that use during

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

may harm the fetus. Citalopram was approved for medical use in the United States in 1998. 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 s ...

. It is available as a

generic medication A generic drug is a pharmaceutical drug that contains the same chemical substance as a drug that was originally protected by chemical patents. Generic drugs are allowed for sale after the patents on the original drugs expire. Because the active ch ...

. In 2022, it was the 40th most commonly prescribed medication in the United States, with more than 15million prescriptions.

Medical uses

Depression

In the United States, citalopram is approved to treat

. Citalopram appears to have comparable efficacy and superior tolerability relative to other antidepressants. In the

National Institute for Health and Clinical Excellence The National Institute for Health and Care Excellence (NICE) is an executive non-departmental public body of the Department of Health and Social Care. As the national health technology assessment body of England, it is responsible for j ...

ranking of ten

s for efficacy and cost-effectiveness, citalopram is fifth in effectiveness (after

mirtazapine Mirtazapine, sold under the brand name Remeron among others, is an atypical antidepressant, atypical tetracyclic antidepressant, and as such is used primarily to treat Depression (mood), depression. Its effects may take up to four weeks but ca ...

escitalopram Escitalopram ( ), sold under the brand names Lexapro and Cipralex, among others, is an antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class. It is mainly used to treat major depressive disorder, generalized ...

venlafaxine Venlafaxine, sold under the brand name Effexor among others, is an antidepressant medication of the serotonin–norepinephrine reuptake inhibitor (SNRI) class. It is used to treat major depressive disorder, generalized anxiety disorder, pani ...

, and

sertraline Sertraline, sold under the brand name Zoloft among others, is an Antidepressant, antidepressant medication of the selective serotonin reuptake inhibitor (SSRI) class used to treat major depressive disorder, generalized anxiety disorder, socia ...

) and fourth in cost-effectiveness. Evidence for the effectiveness of citalopram for treating depression in children is uncertain.

Panic disorder

Citalopram is licensed in the UK and other European countries for

, with or without

agoraphobia Agoraphobia is an anxiety disorder characterized by symptoms of anxiety in situations where the person perceives their environment to be unsafe with no way to escape. These situations can include public transit, shopping centers, crowds and q ...

Other

Citalopram may be used off-label to treat

anxiety Anxiety is an emotion characterised by an unpleasant state of inner wikt:turmoil, turmoil and includes feelings of dread over Anticipation, anticipated events. Anxiety is different from fear in that fear is defined as the emotional response ...

, and

dysthymia Dysthymia ( ), known as persistent depressive disorder (PDD) in the DSM-5-TR and dysthymic disorder in ICD-11, is a psychiatric condition marked by symptoms that are similar to those of major depressive disorder, but which persist for at leas ...

premenstrual dysphoric disorder Premenstrual dysphoric disorder (PMDD) is a mood disorder characterized by emotional, cognitive, and physical symptoms. PMDD causes significant distress or impairment in menstruating women during the luteal phase of the menstrual cycle. The symp ...

body dysmorphic disorder Body dysmorphic disorder (BDD), also known in some contexts as dysmorphophobia, is a mental disorder defined by an overwhelming preoccupation with a perceived flaw in one's physical appearance. In BDD's delusional variant, the flaw is imagined ...

, and

obsessive–compulsive disorder Obsessive–compulsive disorder (OCD) is a mental disorder in which an individual has intrusive thoughts (an ''obsession'') and feels the need to perform certain routines (''Compulsive behavior, compulsions'') repeatedly to relieve the dis ...

. It appears to be as effective as fluvoxamine and paroxetine in obsessive–compulsive disorder. Some data suggest the effectiveness of intravenous infusion of citalopram in resistant OCD. Citalopram is well tolerated and as effective as

moclobemide Moclobemide, sold under the brand names Amira, Aurorix, Clobemix, Depnil and Manerix among others, is a reversible inhibitor of monoamine oxidase A (RIMA) drug primarily used to treat Clinical depression, depression and social anxiety. It is not ...

in social anxiety disorder. There are studies suggesting that citalopram can be useful in reducing aggressive and impulsive behavior. It appears to be superior to placebo for behavioural disturbances associated with dementia. It has also been used successfully for hypersexuality in early Alzheimer's disease. A meta-analysis, including studies with fluoxetine, paroxetine, sertraline, escitalopram, and citalopram versus placebo, showed SSRIs to be effective in reducing symptoms of premenstrual syndrome, whether taken continuously or just in the luteal phase. For alcoholism, citalopram has produced a modest reduction

alcohol Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alco ...

intake and increase in drink-free days in studies of alcoholics, possibly by decreasing desire or reducing the reward. While on its own citalopram is less effective than

amitriptyline Amitriptyline, sold under the brand name Elavil among others, is a tricyclic antidepressant primarily used to treat major depressive disorder, and a variety of pain syndromes such as neuropathic pain, fibromyalgia, migraine and tension headac ...

in the prevention of migraines, in

refractory In materials science, a refractory (or refractory material) is a material that is resistant to decomposition by heat or chemical attack and that retains its strength and rigidity at high temperatures. They are inorganic, non-metallic compound ...

cases, combination therapy may be more effective. Citalopram and other SSRIs can be used to treat hot flashes. A 2009 multisite randomized controlled study found no benefit and some adverse effects in autistic children from citalopram, raising doubts about whether SSRIs are effective for treating repetitive behavior in children with autism. * Some research suggests citalopram interacts with cannabinoid protein-couplings in the rat brain, and this is put forward as a potential cause of some of the drug's antidepressant effects.

Administration

Citalopram is typically taken in one dose, either in the morning or evening. It can be taken with or without food. Its absorption does not increase when taken with food, but doing so can help prevent nausea. Nausea is often caused when the 5-HT₃ receptors actively absorb free serotonin, as this receptor is present within the digestive tract.

Adverse effects

Citalopram theoretically causes side effects by increasing the concentration of

serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...

in other parts of the body (e.g., the intestines). Other side effects, such as increased apathy and emotional flattening, may be caused by the decrease in

dopamine Dopamine (DA, a contraction of 3,4-dihydroxyphenethylamine) is a neuromodulatory molecule that plays several important roles in cells. It is an organic chemical of the catecholamine and phenethylamine families. It is an amine synthesized ...

release associated with increased serotonin. Citalopram is also a mild

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 ...

, which may be responsible for some of its sedating properties. Other common side effects of citalopram include

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 ...

insomnia Insomnia, also known as sleeplessness, is a sleep disorder where people have difficulty sleeping. They may have difficulty falling asleep, or staying asleep for as long as desired. Insomnia is typically followed by daytime sleepiness, low ene ...

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 d ...

, weight changes (usually weight gain), increase in appetite, vivid dreaming, frequent urination, dry mouth, increased

sweating Perspiration, also known as sweat, is the fluid secreted by sweat glands in the skin of mammals. Two types of sweat glands can be found in humans: eccrine glands and apocrine glands. The eccrine sweat glands are distributed over much of the ...

, trembling,

diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

, excessive yawning, severe tinnitus, and

fatigue Fatigue is a state of tiredness (which is not sleepiness), exhaustion or loss of energy. It is a signs and symptoms, symptom of any of various diseases; it is not a disease in itself. Fatigue (in the medical sense) is sometimes associated wit ...

. Less common side effects include

bruxism Bruxism is excessive teeth grinding or jaw clenching. It is an oral Parafunctional habit, parafunctional activity; i.e., it is unrelated to normal function such as eating or talking. Bruxism is a common behavior; the global prevalence of brux ...

vomiting Vomiting (also known as emesis, puking and throwing up) is the 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, gastroenteritis, pre ...

cardiac arrhythmia Arrhythmias, also known as cardiac arrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. Essentially, this is anything but normal sinus rhythm. A resting heart rate that is too fast – above 100 beat ...

blood pressure Blood pressure (BP) is the pressure of Circulatory system, circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term ...

changes, dilated pupils,

mood swing A mood swing is an extreme or sudden change of mood. Such changes can play a positive or a disruptive part in promoting problem solving and in producing flexible forward planning. When mood swings are severe, they may be categorized as part ...

headache A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...

, hyperactivity 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 Balance disorder, disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a ...

. Rare side effects include

convulsions 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 often used as a synony ...

hallucinations A hallucination is a perception in the absence of an external stimulus that has the compelling sense of reality. They are distinguishable from several related phenomena, such as dreaming ( REM sleep), which does not involve wakefulness; pse ...

, severe

allergic reactions Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermatitis, alle ...

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 phototoxicit ...

. If sedation occurs, the dose may be taken at bedtime rather than in the morning. Some data suggest citalopram may cause nightmares. Citalopram is associated with a higher risk of arrhythmia than other SSRIs. Citalopram and other SSRIs can induce a mixed state, especially in those with undiagnosed

bipolar disorder Bipolar disorder (BD), previously known as manic depression, is a mental disorder characterized by periods of Depression (mood), depression and periods of abnormally elevated Mood (psychology), mood that each last from days to weeks, and in ...

. According to an article published in 2020, one of the other rare side effects of Citalopram could be triggering

visual snow syndrome Visual snow syndrome (VSS) is an uncommon neurological condition in which the primary symptom is visual snow, a persistent flickering white, black, transparent, or colored dots across the whole visual field. It is distinct from the ''symptom'' ...

; which does not resolve after the discontinuation of the medicine.

Sexual dysfunction

Sexual dysfunction Sexual dysfunction is difficulty experienced by an individual or partners during any stage of normal sexual activity, including physical pleasure, desire, preference, arousal, or orgasm. The World Health Organization defines sexual dysfunction ...

is often a side effect of SSRIs. Some people experience persistent sexual side effects when taking SSRIs or after discontinuing them. Symptoms of medication-induced sexual dysfunction from antidepressants include difficulty with orgasm, erection, or ejaculation. Other symptoms may be genital anesthesia,

anhedonia Anhedonia is a diverse array of deficits in hedonic function, including reduced motivation or ability to experience pleasure. While earlier definitions emphasized the inability to experience pleasure, anhedonia is currently used by researcher ...

, decreased libido, vaginal lubrication issues, and nipple insensitivity in women. Rates are unknown, and there is no established treatment.

Abnormal heart rhythm

In August 2011, the FDA announced, "Citalopram causes dose-dependent QT interval prolongation. Citalopram should no longer be prescribed at doses greater than 40 mg per day". A further clarification, issued in March 2012, restricted the maximum dose to 20 mg for subgroups of patients, including those older than 60 years and those taking an inhibitor of cytochrome P450 2C19.7.

Endocrine effects

As with other SSRIs, citalopram can cause an increase in serum

prolactin Prolactin (PRL), also known as lactotropin and mammotropin, 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 secr ...

level. Citalopram has no significant effect on insulin sensitivity in women of reproductive age and no changes in glycaemic control were seen in another trial.

Exposure in pregnancy

Antidepressant exposure (including citalopram) during pregnancy is associated with shorter duration of

gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregn ...

(by three days), increased risk of preterm delivery (by 55%), lower birth weight (by 75 g), and lower

Apgar score The Apgar score is a quick way for health professionals to evaluate the health of all newborns at 1 and 5 minutes after birth and in response to resuscitation. It was originally developed in 1952 by an anesthesiologist at Columbia University, ...

s (by <0.4 points). Antidepressant exposure is not associated with an increased risk of spontaneous abortion. It is uncertain whether there is an increased prevalence of septal heart defects among children whose mothers were prescribed an SSRI in early pregnancy.

Overdose

Overdosage may result in vomiting, sedation, disturbances in heart rhythm, dizziness, sweating, nausea, tremors, and rarely amnesia, confusion, coma, or convulsions. Overdose deaths have occurred, sometimes involving other drugs, but also with citalopram as the sole agent. Citalopram and N-desmethylcitalopram may be quantified in blood or plasma to confirm a diagnosis of poisoning in hospitalized patients or to assist in a medicolegal death investigation. Blood or plasma citalopram concentrations are usually in a range of 50-400 μg/L in persons receiving the drug therapeutically, 1000–3000 μg/L in patients who survive acute overdosage, and 3–30 mg/L in those who do not survive. It is the most dangerous of SSRIs in overdose.

Suicidality

In the United States, citalopram carries a

boxed warning In the United States, a boxed warning (sometimes "black box warning", colloquially) is a type of warning that appears near the beginning of the package insert for certain prescription drugs, so called because the U.S. Food and Drug Administratio ...

stating it may increase suicidal thinking and behavior in those under age 24.

Discontinuation syndrome

SSRI discontinuation syndrome has been reported when treatment is stopped. It includes sensory, and gastrointestinal symptoms, dizziness, lethargy, and sleep disturbances, as well as psychological symptoms such as anxiety/agitation, irritability, and poor concentration. Electric shock-like sensations are typical for SSRI discontinuation. Withdrawal symptoms can occur when this medicine is suddenly stopped, such as paraesthesiae, sleeping problems (difficulty sleeping and intense dreams), feeling dizzy, agitated or anxious, nausea, vomiting, tremors, confusion, sweating, headache, diarrhea, palpitations, changes in emotions, irritability, and eye or eyesight problems. Treatment with citalopram should be reduced gradually when treatment is finished.

Interactions

Serotonin syndrome

Citalopram should not be taken with St John's wort,

tryptophan Tryptophan (symbol Trp or W) is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromat ...

5-HTP 5-Hydroxytryptophan (5-HTP), used medically as oxitriptan, is a naturally occurring amino acid and chemical precursor as well as a metabolic intermediate in the biosynthesis of the neurotransmitter serotonin. 5-HTP can be manufactured and us ...

as the resulting drug interaction could lead to

. With St John's wort, this may be caused by compounds in the plant extract reducing the efficacy of the

hepatic The liver is a major metabolic organ (anatomy), organ exclusively found in vertebrates, which performs many essential biological Function (biology), functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of var ...

cytochrome P450 Cytochromes P450 (P450s or CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that mostly, but not exclusively, function as monooxygenases. However, they are not omnipresent; for examp ...

enzymes that process citalopram. Tryptophan and 5-HTP are precursors to serotonin. When taken with an SSRI, such as citalopram, this can lead to levels of serotonin that can be lethal. This may also be the case when SSRIs are taken with SRAs (

serotonin releasing agents A serotonin releasing agent (SRA) is a type of drug that induces the release of serotonin into the neuronal synaptic cleft. A selective serotonin releasing agent (SSRA) is an SRA with less significant or no efficacy in producing neurotransmitter ...

) such as in the case of

MDMA 3,4-Methylenedioxymethamphetamine (MDMA), commonly known as ecstasy (tablet form), and molly (crystal form), is an empathogen–entactogenic drug with stimulant and minor Psychedelic drug, psychedelic properties. In studies, it has been used ...

. It is possible that SSRIs could reduce the effects associated with an SRA since SSRIs stop the reuptake of Serotonin by blocking SERT. This would allow less serotonin in and out of the transporters, thus decreasing the likelihood of

neurotoxic Neurotoxicity is a form of toxicity in which a biological, chemical, or physical agent produces an adverse effect on the structure or function of the central and/or peripheral nervous system. It occurs when exposure to a substance – specifical ...

effects. However, these concerns are still disputed as the exact pharmacodynamic effects of citalopram and MDMA have yet to be fully identified. Citalopram is

contraindicated In medicine, a contraindication is a condition (a situation or factor) that serves as a reason not to take a certain medical treatment due to the harm that it would cause the patient. Contraindication is the opposite of indication, which is a rea ...

in individuals taking MAOIs, owing to a potential for

Other interactions

SSRIs, including citalopram, can increase the risk of bleeding, especially when coupled with

aspirin Aspirin () is the genericized trademark for acetylsalicylic acid (ASA), a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and inflammation, and as an antithrombotic. Specific inflammatory conditions that aspirin is ...

, NSAIDs,

warfarin Warfarin, sold under the brand name Coumadin among others. It is used as an anticoagulant, anticoagulant medication. It is commonly used to prevent deep vein thrombosis and pulmonary embolism, and to protect against stroke in people who ha ...

, or other

anticoagulants An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which h ...

. Taking citalopram with

omeprazole Omeprazole, sold under the brand names Prilosec and Losec, among others, is a medication used in the treatment of gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger–Ellison syndrome. It is also used to prevent up ...

may cause higher blood levels of citalopram. This is a potentially dangerous interaction, so dosage adjustments may be needed or alternatives may be prescribed.

Pharmacokinetics

Citalopram is considered safe and well tolerated in the therapeutic dose range. Distinct from some other agents in its class, it exhibits linear

pharmacokinetics Pharmacokinetics (from Ancient Greek ''pharmakon'' "drug" and ''kinetikos'' "moving, putting in motion"; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to describing how the body affects a specific su ...

and minimal

drug interaction In pharmaceutical sciences, drug interactions occur when a drug's mechanism of action is affected by the concomitant administration of substances such as foods, beverages, or other drugs. A popular example of drug–food interaction is the effect ...

potential, making it a better choice for the elderly or

comorbid In medicine, comorbidity refers to the simultaneous presence of two or more medical conditions in a patient; often co-occurring (that is, concomitant or concurrent) with a primary condition. It originates from the Latin term (meaning "sicknes ...

patients.

Stereochemistry

Citalopram has one

stereocenter In stereochemistry, a stereocenter of a molecule is an atom (center), axis or plane that is the focus of stereoisomerism; that is, when having at least three different groups bound to the stereocenter, interchanging any two different groups cr ...

, to which a 4-fluoro

phenyl group In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula , and is often represented by the symbol Ph (archaically φ) or Ø. The phenyl group is closely related to benzene and can be viewed as a benzene ...

and an ''N, N''-dimethyl-3-aminopropyl group bind. As a result of this

chirality Chirality () is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable fro ...

, the molecule exists in (two)

enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...

ic forms (mirror images). They are termed ''S''-(+)-citalopram and ''R''-(–)-citalopram. Citalopram is sold as a

racemic In chemistry, a racemic mixture or racemate () is a mixture that has equal amounts (50:50) of left- and right-handed enantiomers of a chiral molecule or salt. Racemic mixtures are rare in nature, but many compounds are produced industrially as r ...

mixture, consisting of 50% (''R'')-(−)-citalopram and 50% (''S'')-(+)-citalopram. Only the (''S'')-(+) enantiomer has the desired antidepressant effect.

Lundbeck H. Lundbeck A/S, commonly referred to as Lundbeck, is a Denmark, Danish international pharmaceutical company engaged in the research, development, manufacturing, marketing and sale of pharmaceuticals across the world. The company’s products ar ...

now markets the (''S'')-(+) enantiomer, the generic name of which is

. Whereas citalopram is supplied as the hydrobromide, escitalopram is sold as the

oxalate Oxalate (systematic IUPAC name: ethanedioate) is an anion with the chemical formula . This dianion is colorless. It occurs naturally, including in some foods. It forms a variety of salts, for example sodium oxalate (), and several esters such as ...

salt (hydrooxalate). In both cases, the

salt In common usage, salt is a mineral composed primarily of sodium chloride (NaCl). When used in food, especially in granulated form, it is more formally called table salt. In the form of a natural crystalline mineral, salt is also known as r ...

forms of the amine make these otherwise

lipophilic Lipophilicity (from Greek language, Greek λίπος "fat" and :wikt:φίλος, φίλος "friendly") is the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such compounds are c ...

compounds water-soluble.

Metabolism

Citalopram is metabolized in the liver mostly by

CYP2C19 Cytochrome P450 2C19 (abbreviated CYP2C19) is an enzyme protein. It is a member of the CYP2C subfamily of the cytochrome P450 mixed-function oxidase system. This subfamily includes enzymes that catalyze metabolism of xenobiotics, including some ...

, but also by

CYP3A4 Cytochrome P450 3A4 (abbreviated CYP3A4) () is an important enzyme in the body, mainly found in the liver and in the intestine, which in humans is encoded by ''CYP3A4'' gene. It organic redox reaction, oxidizes small foreign organic molecules ( ...

and

CYP2D6 Cytochrome P450 2D6 (CYP2D6) is an enzyme that in humans is encoded by the ''CYP2D6'' gene. ''CYP2D6'' is primarily expressed in the liver. It is also highly expressed in areas of the central nervous system, including the substantia nigra. CYP2 ...

. Metabolites desmethylcitalopram and didesmethylcitalopram are significantly less energetic and their contribution to the overall action of citalopram is negligible. The half-life of citalopram is about 35 hours. Approximately 80% is cleared by the liver and 20% by the kidneys. The elimination process is slower in the elderly and in patients with liver or

kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

. With once-daily dosing, steady plasma concentrations are achieved in about a week. Potent inhibitors of CYP2C19 and 3A4 might decrease citalopram clearance. Tobacco smoke exposure was found to inhibit the biotransformation of citalopram in animals, suggesting that the elimination rate of citalopram is decreased after tobacco smoke exposure. After intragastric administration, the half-life of the

mixture of citalopram was increased by about 287%. Citalopram metabolism

History

Citalopram was first synthesized in 1972 by chemist Klaus Bøgesø and his research group at the pharmaceutical company

and was first marketed in 1989 in Denmark. It was first marketed in the US in 1998. The original

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling discl ...

expired in 2003, allowing other companies to legally produce and market generic versions.

Society and culture

Brand names

Citalopram is sold under these brand names: * Akarin (Denmark, Nycomed) * C Pram S (India) * Celapram (Australia, New Zealand), * Celexa (U.S. and Canada, Forest Laboratories, Inc.) * Celica (Australia) * Ciazil (Australia, New Zealand) * Cilate (South Africa) * Cilift (South Africa) * Cimal (South America, by Roemmers and Recalcine) * Cipralex (Europe, South Africa) * Cipram (Denmark, Turkey, H. Lundbeck A/S) * Cipramil (Australia, Brazil, Belgium, Chile, Finland, Germany, Netherlands, Iceland, Ireland, Israel, New Zealand, Norway, Russia, South Africa, Sweden, United Kingdom) * Cipraned, Cinapen (Greece) * Ciprapine (Ireland) * Ciprotan (Ireland) * Citabax, Citaxin (Poland) * Cital (Poland) * Citalec (Czech Republic, Slovakia) * Citalex (Iran, Serbia) * Citalo (Australia, Egypt, Pakistan) * Citalopram (Canada, Denmark, Finland, Germany, Ireland, The Netherlands, New Zealand, Spain, Sweden, Switzerland, United Kingdom, U.S.) * Citol (Russia, Turkey) * Citox (Mexico) * Citrol (Europe and Australia) * Citta (Brazil) * Dalsan (Eastern Europe) * Denyl (Brazil) * Depram (Egypt) * Elopram (Italy) * Estar (Pakistan) * Humorup (Argentina) * Humorap (Peru, Bolivia) * Lopraxer (Greece) * Oropram (Iceland, Actavis), * Opra (Russia) * Pram (Russia) * Pramcit (Pakistan) * Procimax (Brazil) * Recital (Israel, Thrima Inc. for Unipharm Ltd.) * Sepram (Finland) * Seropram (various European countries, including the Czech Republic) * Szetalo (India) * Talam (Europe and Australia) * Temperax (Argentina, Chile, Peru) * Vodelax (Turkey) * Zentius (South America, by Roemmers and Recalcine) * Zetalo (India) * Cipratal (Kuwait, GCC) * Zylotex (Portugal)

European Commission fine

On 19 June 2013, the

European Commission The European Commission (EC) is the primary Executive (government), executive arm of the European Union (EU). It operates as a cabinet government, with a number of European Commissioner, members of the Commission (directorial system, informall ...

imposed a fine of €93.8 million on the Danish pharmaceutical company

, plus a total of €52.2 million on several generic pharmaceutical-producing companies. This was in response to Lundbeck entering an agreement with the companies to delay their sales of generic citalopram after Lundbeck's

on the drug had expired, thus reducing competition in breach of European

antitrust law Competition law is the field of law that promotes or seeks to maintain market competition by regulating anti-competitive conduct by companies. Competition law is implemented through public and private enforcement. It is also known as antitrust ...

Other uses

Citalopram is also a parasiticide.

Schistosomula ''Schistosoma'' is a genus of trematodes, commonly known as blood flukes. They are parasitic flatworms responsible for a highly significant group of infections in humans termed ''schistosomiasis'', which is considered by the World Health Organi ...

have high mortality when treated with citalopram.

References

{{Authority control Drugs developed by AbbVie Antidepressants Benzonitriles CYP2D6 inhibitors Dimethylamino compounds 4-Fluorophenyl compounds Isobenzofurans Selective serotonin reuptake inhibitors Sigma agonists Wikipedia medicine articles ready to translate

Medical uses

Depression

Panic disorder

Other

Administration

Adverse effects

Sexual dysfunction

Abnormal heart rhythm

Endocrine effects

Exposure in pregnancy

Overdose

Suicidality

Discontinuation syndrome

Interactions

Serotonin syndrome

Other interactions

Pharmacokinetics

Stereochemistry

Metabolism

History

Society and culture

Brand names

European Commission fine

Other uses

See also

References