Neuroleptic Malignant Syndrome vs Serotonin Syndrome: Can They Be Distinguished Without an Underlying Etiology?

Neuroleptic malignant syndrome (NMS) and serotonin syndrome (SS) are rare but potentially fatal conditions associated with the treatment of psychotropic medications. Neuroleptic malignant syndrome is believed to be caused by a reduction in dopaminergic activity secondary to drug-induced dopaminergic blockage, whereas SS results from an excess of central nervous system (CNS) serotonin activity, usually because of serotonin agonist polypharmacy or a drug-drug interaction involving serotonin agonist drugs.(1,2)