Venlafaxine: Loss of Antidepressant Effect and Its Management

Sir: The antidepressant profile of venlafaxine includes a broad range of clinical activity, as its effect is not influenced by factors such as the presence of melancholic features, age, gender, severity, or duration of depression. A recent analysis of the treatments of major depression revealed that venlafaxine had the highest efficacy rates and lowest dropout rates when compared with tricyclics and serotonin reuptake inhibitors. Up to one third of patients with rigorously defined treatmentresistant depression show a favorable response to venlafaxine, but nearly half of these patients are unable to sustain the antidepressant effect during the first 3 months of treatment.