According to severity of depressive symptomatology 14 inpatients with major depressive disorder (RDC) were assigned to 2 groups of 7 patients each with 6 of them receiving fluoxetine 60-80 mg/day and 1 receiving placebo in each group in a double-blind manner. After the treatment period of 35 days clinical improvement as assessed by standardized rating scales was more pronounced in the moderately depressed patients. There were no substantial side-effects in the 2 groups. These findings corroborate previous results from outpatient studies in more heterogeneous patient samples demonstrating safety and antidepressive efficacy of fluoxetine.