Pindolol augmentation of treatment-resistant depressed patients

Background: Recent uncontrolled reports describe a dramatic and rapid improvement of depressive symptoms in patients treated with the combination of pindolol and serotonin selective reuptake inhibitors or monoamine oxidase inhibitors. The present study attempts to replicate those findings. Method: Ten outpatients with current DSM-III-R major depressive disorder who had failed to obtain or maintain an appropriate response to an adequate trial of antidepressant drug were included in a randomized double-blind, placebo- controlled, crossover study. Subjects received pindolol 2.5 mg p.o. t.i.d. or placebo for 2 weeks in addition to their current antidepressant. Clinical monitoring, vital signs, and behavioral ratings were performed weekly for the duration of the study. Results: Pindolol was well tolerated by all patients. None of the subjects experienced significant symptom worsening during the addition of either placebo or active drug. At the end of the 2-week trial, there was no statistically significant difference between pindolol augmentation and placebo. Two patients had a categorical response during placebo treatment. No categorical responses were observed during pindolol augmentation. Conclusion: This study failed to replicate the rapid and dramatic response to pindolol augmentation in treatment-resistant depressed patients.