Serum levels of clomipramine and desmethylclomipramine and clinical improvement in panic disorder

Several placebo-controlled trials have shown the efficacy of clomipramine ( CMI) in panic disorder. However, none has investigated the relationship bet ween CMI, and desmethylclomipramine (DCMI) plasma levels, and outcome. In t his trial, 41 patients meeting the DSM-III-R criteria for panic disorder wi th/without agoraphobia received 50-200 mg of CMI daily in a single-blind, f lexible dose regimen for 14 weeks. At the end of treatment, 97% of the pati ents were free of panic attacks. Patients were classified into two groups o f improvement according to the panic symptom items of the 'Patient-Rated An xiety Scale'. A repeated-measures analysis of variance suggested a signific ant association between outcome and serum DCM level/daily dose ratio as wel l as total serum level/daily dose. Patients with intense improvement showed DCMI and total serum levels lower than those with moderate improvement. Th e results indicate the importance of monitoring clomipramine and desmethylc lomipramine serum levels in this disorder.