Neuroleptic Malignant Syndrome By David Tanen, MD, David Geffen School of Medicine at UCLA Reviewed / Revised Mar 2023 View Patient Education Etiology Symptoms and Signs Diagnosis Treatment Key Points Topic Resources Drugs That Can Cause Neuroleptic... Neuroleptic malignant syndrome is characterized by altered mental status, muscle rigidity, hyperthermia, and autonomic hyperactivity that occur when certain neuroleptic drugs are used.