Clinical and biochemical effects of citalopram, a selective 5-HT reuptake inhibitor--a dose-response study in depressed patients.

Citalopram is a bicyclic phtalane derivative. In animal experiments, citalopram has been demonstrated to possess a potent and highly selective inhibitory effect on serotonin reuptake. Several studies in man have indicated that citalopram given in daily doses of 40-60 mg has antidepressant properties and few side effects. The present double-blind study investigated the effects of three doses of citalopram (5 mg, 25 mg, and 50 mg) on depressive symptoms and various biochemical variables in 26 depressive patients. A significant reduction of the clinical ratings of depressive symptoms occurred at all dose levels. In endogenously depressed patients, a dose of 25 or 50 mg daily seemed to have the most pronounced antidepressive effect. The side effects were few and not related to dose level. A highly significant decrease in 5-HIAA in the CSF was found. MO-PEG in the CSF was also significantly decreased, while HVA in the CSF was increased. In addition, a significant decrease in the plasma concentrations of valine, leucine, tyrosine, and histidine was found. None of the biochemical effects was dose-dependent. The complex pattern of biochemical effects indicate that the amelioration of depressive symptoms might be related to effects of citalopram on central monoaminergic mechanisms and peripheral amino acid concentrations.

RCT Entities:   Population Interventions Outcomes