The use of herbal medicines remains controversial despite their wide use by consumers. By U.S. standards few of these products have been sufficiently evaluated in scientific studies to determine with certainty their efficacy and safety. The authors review the herbal medicines with reputed psychiatric indications and discuss the potential adverse events with which physicians should be familiar. Whatever their potential benefits, some of these herbal products have potentially serious side effects, and many can interact with prescription medications. Patients frequently do not tell their physicians about their use of alternative medicines, and practitioners must ask specifically about products patients may be taking for health promotion and disease prevention as well as for the treatment of the presenting complaint.