Neuroleptic Malignant Syndrome - Causes

Causes

NMS is usually caused by neuroleptic drug use, and a wide range of drugs can result in NMS. Individuals using haloperidol or chlorpromazine are reported to be at greatest risk. NMS may also occur in people taking dopaminergic drugs (such as levodopa) for Parkinson's disease, most often when the drug dosage is abruptly reduced. In addition, other drugs with anti-dopaminergic activity, such as the antiemetic metoclopramide, can induce NMS. Even drugs without known anti-dopaminergic activity have been associated with NMS; examples include amoxapines and lithium. Also, desipramine, dothiepin, phenelzine, tetrabenazine, and reserpine have been known to trigger NMS. At the molecular level, NMS is caused by a sudden, marked reduction in dopamine activity, either from withdrawal of dopaminergic agents or from blockade of dopamine receptors.