Citalopram

Citalopram
Systematic (IUPAC) name
(RS)-1-[3-(dimethylamino)propyl]-1-
(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile
Clinical data
AHFS/Drugs.com
MedlinePlus
Pregnancy cat.
Legal status
  • Prescription only
Routes Oral
Pharmacokinetic data
Bioavailability 80%
peak at 4 hours[1]
Metabolism hepatic (CYP3A4 & CYP2C19)
Half-life 35 hours
Excretion Mostly as unmetabolized citalopram, partly DCT and traces of DDCT in urine
Identifiers
CAS number  YesY
ATC code N06
PubChem
DrugBank
ChemSpider  YesY
UNII  YesY
KEGG  YesY
ChEBI  YesY
ChEMBL  YesY
Chemical data
Formula C20H21FN2O 
Mol. mass 324.392 g/mol
 YesY   

Citalopram ( or ; brand names: Celexa, Cipramil) is an antidepressant drug of the selective serotonin reuptake inhibitor (SSRI) class. It has U.S. Food and Drug Administration (FDA) approval to treat major depression,[1] which it received in 1998[2] and is prescribed off-label for other conditions. In Australia, the UK, Germany, Portugal, Poland, and most European countries it is licensed for depressive episodes and panic disorder with or without agoraphobia. In Spain it is also used for obsessive-compulsive disorder.

Medical uses

Citalopram HBr tablets in 20 mg (coral, marked 508) and 40 mg (white, marked 509), and a United States one-cent coin (size 19.05mm/0.75").

Depression

In NICE (National Institute for Health and Clinical Excellence) ranking of 10 antidepressants for efficacy and cost-effectiveness[28] citalopram is fifth in effectiveness (after mirtazapine, escitalopram, venlafaxine and sertraline) and fourth in cost effectiveness. The ranking results were based on the meta analysis by Andrea Cipriani[29] In another analysis by Cipriani citalopram turned out to be more efficacious than paroxetine and reboxetine and more acceptable than tricyclics, reboxetine and venlafaxine, however it seemed to be less efficacious than escitalopram.[5]

Evidence for effectiveness of citalopram for treating depression in children is equivocal.[30][31]

There has been controversy regarding the efficacy of antidepressants in treating depression depending on its severity and duration, as discussed in the Selective Serotonin Reuptake Inhibitor article.

Panic disorder

Citalopram is licensed in the UK and other European countries [32][33] for panic disorder, with or without agoraphobia. The dose is 10 mg/d for a week, increasing to 20–30 mg/d, with a maximum of 40 mg/d.[34]

Off-label

Citalopram is frequently used off-label to treat anxiety, panic disorder, dysthymia[35] premenstrual dysphoric disorder, body dysmorphic disorder and obsessive–compulsive disorder.[12]

It has been shown to be effective in 85% of patients with GAD (generalized anxiety disorder), including some who had failed with other SSRIs[36] It also appears to be as effective as fluvoxamine and paroxetine in obsessive-compulsive disorder.[37] Some data suggests the effectiveness of intravenous infusion of citalopram in resistant OCD.[38] Citalopram 40 mg/d is well tolerated and as effective as moclobemide in social anxiety disorder.[39] There are studies suggesting that citalopram can be useful in reducing aggressive and impulsive behavior.[40][41] It appears to be superior to placebo for behavioural disturbances associated with dementia.[42] It has also been used successfully for hypersexuality in early Alzheimer’s disease.[43]

A meta analysis, including studies with fluoxetine, paroxetine, sertraline, escitalopram and citalopram versus placebo, showed that SSRIs are effective in reducing symptoms of premenstrual syndrome (PMS), whether taken continuously or just in the luteal phase.[44] Citalopram has produced a modest reduction in alcoholic drink intake and increase in drink-free days in studies of alcoholics, possibly by decreasing desire or reducing the reward.[45]

Citalopram has been found to reduce the symptoms of diabetic neuropathy.[23]

While on its own citalopram is less effective than amitriptyline in the prevention of migraines, in refractory cases combination therapy may be more effective.[24]

Citalopram and other SSRIs can be used to treat hot flashes.[25]:107

A 2009 multisite randomized controlled study found no benefit and some adverse effects in autistic children from citalopram, raising doubts whether SSRIs are effective for treating repetitive behavior in children with autism.[26]

Some research suggests that 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 effect.[27]

Administration

Citalopram is typically taken in one dose, either in the morning or evening. Citalopram can be taken with or without food. The absorption of citalopram does not increase when taken with food,[1] but doing so can help prevent nausea. Nausea is often caused when the 5HT3 receptors actively absorb free serotonin, as this receptor is present within the digestive tract.[46] The 5HT3 receptors stimulate vomiting. This side effect, if present, should subside as the body adjusts to the medication.

Citalopram is considered safe and well tolerated in the therapeutic dose range. Distinct from some other agents in its class, citalopram exhibits linear pharmacokinetics and minimal drug interaction potential, making it a better choice for the elderly or comorbid patients.[47]

Adverse effects