Cocaine use, frequently associated with other substance abuse, is becoming more common in the pregnant patient. These patients are more likely to experience peripartum complications. A case of hypertension and pulmonary oedema in such a patient, possibly triggered by ketamine, is reported. A tumultuous course in the intensive care unit was resolved when the patient's hypertension and sympathetic reactivity were successfully treated with barbiturates. A number of factors supported a diagnosis of barbiturate withdrawal in this patient, its onset also was related temporally to ketamine administration. Hypertension should be considered a sign of acute barbiturate withdrawal. If a history of cocaine use, particularly crack cocaine, is elicited, one should suspect multiple substance abuse and be especially cautious when administering ketamine.