Citalopram for treatment-resistant obsessive-compulsive disorder

We investigated the comparative efficacy of citalopram vs. citalopram admin istered with clomipramine, in treatment-resistant obsessive-compulsive diso rder (OCD). Sixteen adult outpatients participated in a 90-day, randomized, open-label trial. Eligible patients were aged 18 to 45 years, had moderate to severe D SM-III-R OCD of greater than or equal to one year's duration, a baseline Ya le-Brown scale (Y-BOCS) score of greater than or equal to 25 and no other a ctive axis 1 diagnosis, and had failed adequate clomipramine and fluoxetine trials. The citalopram-plus-clomipramine group (n = 9) experienced a significantly larger percent decrease in mean Y-BOCS score by day 90 than the citalopram alone group (n = 7). Only one citalopram patient decreased her score by gre ater than or equal to 35%, and two by greater than or equal to 25%. All nin e citalopram-plus-clomipramine patients experienced decreases of greater th an or equal to 35%. Side effects were mild to moderate in bath groups. We a lso treated with citalopram six OCD patients who had not tolerated fluoxeti ne alone and clomipramine alone; three achieved Y-BOCS score decreases of g reater than or equal to 35% at 90 days. Since citalopram does not significantly affect clomipramine metabolism, the improvement in the combined drug group is unlikely to have resulted from i ncreased plasma clomipramine levels. Double-blind controlled trials are nee ded of citalopram in OCD, and of combining citalopram with clomipramine in treatment-resistant OCD. (C) 1999 Elsevier, Paris.