Abstract

The efficacy of imipramine hydrochloride (IMI) for adolescents with major depressive illness meeting Research Diagnostic Criteria (RDC) and DSM-III criteria was assessed in an open-label trial of 35 inpatients. Patients were treated for 6 weeks up to a target dosage of 5 mg/kg/day and assessed weekly by the Hamilton Rating Scale for Depression (HAM-D) and Clinical Global Impressions Improvement scale (CGI). A total of 34 patients in the sample completed the trial, 28 achieving the full target dosage (mean = 222 mg; mean IMI plus desmethylimipramine (DMI) plasma level = 237 ng/ml). Among 24 nondelusional patients, only one third were considered responders based on pattern analysis of the time of onset and persistence of symptom reduction. Among 10 delusional patients, the response rate was 10 percent. Although total IMI plus DMI plasma level did not differ between responders and nonresponders, no responder had a level below 180 ng/ml. In univariate linear regression analysis, no single variable was predictive of response status at 6 weeks. These findings underscore the importance of a comprehensive study of the potency of antidepressant compounds in adolescents and the need for further investigation of psychobiological process mediating drug effects.