Weight gain is a significant problem for many patients taking various psychotropic medications. The U.S. Food and Drug Administration (FDA) has approved certain medications for the treatment of obesity. Other medications known to be associated with weight loss could be used for treating obesity, although they are not FDA approved for this indication. This article briefly describes the sympathomimetic, antidepressant, anticonvulsant, histamine-modulating, antidiabetic, and gastrointestinal drugs that have been found to cause weight loss and might be considered for adjunctive use in the overall management of psychotropic drug-related weight gain. However, even if such drugs are effective, all patients should receive ongoing dietary and physical activity counseling.