We present the case of a 35-year-old man who developed symptoms of the neuroleptic malignant syndrome (NMS) after taking prescribed, moderately high, therapeutic doses of haloperidol. When brought to the emergency department, he was comatose, hypotensive, and had rigid muscle tone and a core body temperature of 42.2 C. Although initial treatment was supportive, intubation, ventilator support, and further care in the intensive care unit were necessary. Ensuing disseminated intravascular coagulation was treated successfully and the patient was weaned from the ventilator on the third day after admission. He was discharged from the hospital 11 days after admission. Recently recognized drug therapy for NMS, such as bromocriptine mesylate and dantrolene sodium, was not used in this case.