Neuroleptic Malignant Syndrome at the Crossroads of Haloperidol and Polysubstance Abuse: A Case Report

Abstract

This case reports a rare adverse reaction, Neuroleptic Malignant Syndrome (NMS), and its diagnostic challenge. The main objectives are to present the clinical symptoms and laboratory findings during the course of the case, discuss the differential diagnosis and diagnostic ambiguity arising in the case, and summarize the early recognition and role of clinicians in timely diagnosis and management of the adverse reaction. The Neuroleptic Malignant Syndrome is a rare and life-threatening adverse reaction caused by certain antipsychotics. Reporting a case of 24-year-old male at the Department of Emergency Medicine, PESUIMSR, Bangalore, India, who had complaints of tremors, sleeplessness, agitation, and weakness. For this neuropsychiatric condition, he was treated with multiple doses of Haloperidol. After two days of administering Haloperidol, he developed hyperthermia, severe muscle rigidity, tachycardia, diaphoresis, and altered sensorium. Initially, it was unclear whether these symptoms are Haloperidol- induced or due to substance abuse withdrawal. Laboratory data showed peak levels of Creatine Phosphokinase (CPK) of about 15019 U/L, indicating severe muscle damage, considered as the hallmark diagnosis of NMS. The causative drug haloperidol was immediately stopped. The patient was treated with lorazepam, bromocriptine, plenty of IV fluids, and symptomatic treatment. The clinical symptoms of agitation and tremors improved, higher levels of CPK was decreased, body temperature and heart rate decreased gradually and the patient was afebrile, referred to primary neuropsychiatric centre for further treatment. Since both symptoms of NMS and substance abuse withdrawal overlap, this case poses a significant diagnostic challenge.