Phenothiazine drugs have a potent sedative action, a marked antiemetic effect, and an apparent synergism with narcotics, barbiturates, and anesthetic agents. Preanesthetic medication with promethazine, scopolamine, and reduced doses of meperidine afforded optimal sedation without significant respiratory and circulatory depressions. Promethazine practically eliminated nausea and emesis in both the preoperative and operative periods, while the incidence of postoperative nausea and emesis after general anesthesia was reduced markedly. Induction and maintenance of general anesthesia was facilitated by promethazine, which appeared to reduce requirements of general anesthetic agents. Mild to moderate hypertension occurred in a few patients after the intravenous administration of promethazine; these rises in blood pressure were transient, without effect on the infant, and could not be explained. A number of patients presented bizarre athetoid-type movements and localized muscle twitchings after receiving promethazine; the muscular phenomena were easily controlled with small doses of intravenously given meperidine. In view of the proved epileptogenic properties of phenothiazine drugs, promethazine should not be given to patients with a history or evidence of preeclampsia, epilepsy, convulsions, intracranial trauma, and severe hypertension.