Medications with central dopamine antagonist properties are in wide use in treating a variety of medical symptoms. Some of the most commonly used are metoclopramide (Reglan), prochlorperazine (Compazine), droperidol (Inapsine), and promethazine (Phenergan). The major adverse neuropsychiatric effects seen with these medications are acute dystonias, akathisia, parkinsonian symptoms, and neuroleptic malignant syndrome. These effects are often unrecognized or misdiagnosed by the primary physician as functional psychiatric disorders. The authors present four cases in which adverse neuropsychiatric effects from metoclopramide and prochlorperazine occurred with patients in the general hospital, and they discuss their initial misdiagnosis and subsequent identification and treatment by the consulting psychiatrist. The literature is reviewed on the adverse neuropsychiatric effects of metoclopramide and prochlorperazine, with attention to patient populations at risk. The authors believe that there is a key role in this area for the consulting psychiatrist, who can provide diagnostic clarity, advice on management, and ongoing staff education.