Neuroleptic Malignant Syndrome Caused by Long Term Intake of Haloperidol

Neuroleptic malignant syndrome (NMS) is a fatal complication most often caused by an adverse reaction to neuroleptic or antipsychotic drugs, and is mostly brought out in the initial stage of medication. Late onset NMS after long term intake of neuroleptics is uncommon, and the neurochemical mechanism is undiscovered. We report a patient of late onset NMS after a long term intake of haloperidol who was successfully treated with dantrolene and bromocriptine.