The purpose of the present study was to assess the efficacy and tolerability of citalopram in the acute treatment of children and adolescents with obsessive compulsive disorder (OCD) during an 8-week, open-label study. Fifteen patients (six female, nine male) with a mean age of 12.1 +/- 3.3 years (range: 6-17 years) were treated with citalopram (range of dose: 20-30 mg/day, mean dose: 24 +/- 5.5 mg/day). The children's version of the Yale-Brown Obsessive-Compulsive scale (CY-BOCS) was rated at the baseline, at the 4th week and at the 8th week of treatment. Fourteen patients had a decrease in total score of CY-BOCS from baseline to the 4th week of treatment (P < 0.01) and the 8th week of treatment (P < 0.01). Sedation (n = 1) and insomnia (n = 1) were reported in the first weeks of treatment. The primary data suggest the efficacy and tolerability of citalopram in young patients with OCD.