Total sleep deprivation (TSD) has been used in association with lithium salts and with serotonergic and noradrenergic antidepressants, leading to sustained improvements in patients affected by major depression. Current theories on the neurobiological mechanism of action of TSD propose a major role for enhanced dopamine activity. To test the clinical relevance of dopaminergic enhancement in TSD, we treated a homogeneous sample of 28 bipolar depressed patients with three cycles of TSD combined with placebo or with the dopaminergic antidepressant amineptine. Changes in mood over time were rated with self-administered visual analogue scales and with the Montgomery-Asberg Depression Rating Scale. Patients showed improved mean daily-mood scores after TSD, an effect that was highest at the first cycle and decreased with treatment repetition. Amineptine enhanced the effects of TSD on perceived mood during the first two TSD cycles, but patients in the placebo and amineptine groups showed comparable results at the end of the treatment. Despite its theoretical importance, the clinical usefulness of combining TSD with a dopaminergic agent must be questioned.