Age-related differences in the side effect profile of citalopram

The authors evaluated the autonomic and cardiovascular side effects of citalopram with particular emphasis on their relation to the age of treated patients. The data that formed the basis for the U.S. Food and Drug Administration approval of citalopram were provided by Lundbeck (Copenhagen, Denmark). This database included placebo-controlled short- and long-term studies in major depressed patients. The list of side effects comprised all "heart rate and rhythm disorders" as well as "autonomic nervous system disorders" that had been reported by at least 5% more than that reported for the placebo group of subjects. The database encompassed 1344 subjects treated with citalopram (20-60 mg/day) for a period of no less than 6 weeks. Statistically significant age-related distribution was found for five side effects: bradycardia, nausea, diarrhea, sweating and headache. Bradycardia was more prevalent in elderly (>65 years) patients as compared to the younger population (2.4% vs. 0.2%, P<.05), whereas gastrointestinal side effects, sweating and headache were less prevalent in the elderly. The age-related differences in the side effect profile may be attributable to altered sensitivity of the serotonergic system.