Citalopram--a Review of Pharmacological and Clinical Effects

Objective: To provide clinicians with a critical evaluation of citalopram, a selective serotonin reuptake inhibitor (SSRI) that has been available in Canada since March 1999.

Data Sources: Commercial searches (MEDLINE and BiblioTech) and an "in-house" search (InfoDrug) were used to find published English-language references for clinical and preclinical publications. There was no restriction of publication dates. Primary index terms used were: pharmacological properties, receptors, pharmacological selectivity, pharmacokinetics, age-related pharmacokinetics, sex-related pharmacokinetics, renal dysfunction, hepatic dysfunction, cytochrome activity, drug interactions, adverse reactions, antidepressant switching, precautions, overdose, drug discontinuation, children, geriatric, depression, combination therapy, placebo control, refractory depression, anxiety disorders and medical disorders.

Study Selection: A total of 74 studies were reviewed. Twenty-one of these studies specifically examined the clinical efficacy and tolerability of citalopram in depressive disorders as well as other disorders. In depressive disorders, clinical studies were required to have either placebo or active comparison controls for a minimum of 3 weeks. For other disorders, in the absence of double-blind trials, open-label studies were included. Pharmacological studies were limited to animal studies focusing on citalopram's selectivity and receptor specificity, and positron emission tomography studies were incorporated to include human pharmacological data. Pharmacokinetic studies focused on the metabolism, safety and tolerability of citalopram, specifically with reference to adverse reactions, drug interactions and overdose in addition to citalopram's effect on vulnerable populations, such as children, the elderly and patients with metabolic diseases.

Data Extraction: Data on clinical studies were summarized according to test measures, study duration and outcome of study. Pharmacokinetic and pharmacodynamic studies were summarized according to properties and interactions. Adverse reactions were extracted to outline citalopram's safety profile.

Data Synthesis: Citalopram is an SSRI antidepressant with a more specific and selective pharmacological profile than other antidepressants of its class. It is well tolerated, and drug interactions are not a significant concern. It is also reasonably safe for populations vulnerable to pharmacokinetic effects, such as the elderly and patients with metabolic diseases. In addition to its tolerability, citalopram is effective in the treatment of major depression, other depressive disorders and panic disorder. It has the potential to effectively treat other anxiety disorders and substance-use disorders; in addition, it may be useful in several medical conditions.

Conclusions: There is evidence to support the role of citalopram as a well-tolerated and effective SSRI antidepressant. There is a need for further evaluation of its role in psychiatric disorders other than major depressive disorder.