Ranitidine, a widely used drug, is known to be well tolerated. This case report illustrates a severe anaphylactic reaction after a single intravenous dose of 50 mg ranitidine during the emergency cesarean section under spinal anesthesia. Anaphylaxis was successfully managed with Inj. adrenaline, Inj. hydrocortisone, ventilatory, and inotropic support following which she had a full recovery. Awareness of this rare but fatal adverse reaction to this commonly used drug could help in early recognition of the event if faced suddenly.