Seven of nine depressed patients experienced a 4.3-fold increase in rated euphoria and activation following 30 mg d-amphetamine in a replicated dose, double blind study. d-Amphetamine was 2 to 2.3-fold more effective in producing activation, euphoria, and antidepressant effects than the same dose of l-amphetamine. Co-treatment with lithium carbonate produced a 60% (P less than 0.001) attenuation of the activation and euphoria responses to d-amphetamine. The responses to l-amphetamine were almost completely abolished by lithium. This study raises the possibility of lithium carbonate use as an adjunct in the treatment of amphetamine addiction.