NMS, how often does it happen?


..and what do you do about the hyperthermic crisis? cooling blankets? tylenol? I'm under the impression it's pretty rare...

Thunderwolf, MSN, RN

6 Articles; 6,621 Posts

Specializes in Med-Surg, Geriatric, Behavioral Health. Has 32 years experience.

i see no one has answered you yet. well, here it goes.

nms or neuroleptic malignant syndrome prevalence is estimated as 0.07-1.4% for patients exposed to neuroleptic medication. typically seen in about 4 weeks of exposure, but can occur at any time within the course of treatment length. estimated, depending upon your sources, as being 10-30% fatal for these patients. the higher the potency of the medication, the higher the risk. men appear to be more at risk for the syndrome than women. it also needs to be differentiated from serotonin syndrome which can mimic it (review both syndromes and their signs & symptoms, heavy overlap). the main differentiation is that shivering, gi symptoms, and less muscle rigidity appear to be the characteristic difference with serotonin syndrome.,..whereas, more significant muscle rigidity appear more classic with nms. i mention both syndromes because many patients are on many meds at the same time...antidepressants and antipsychotics together. nms needs to be differentiated from heat stroke as well, especially during the warmer months. how many folks with schizophrenia have you seen that seem to bundle themselves up in layers of clothes, even in the summer? i have seen this more than i can count. heat stroke is typically seen with the following symptoms: dry skin, limb flaccidity, and lower than normal blood pressure. the reverse is true with nms. dystonia and dysphagia may also be present in nms due to the severe muscle rigidity. there is no way to predict the course of nms if present...if it will be mild or fatal. fever can range from very low grade to brain boiling. so, the first step in treatment is to remove the patient from any antipsychotic drugs being taken and to treat fever aggressively (cooling blankets and hydration). meds like dantrium, parlodel, or amantadine are often used for the syndrome. ventilatory support may also be needed. many cases require intensive care...so, this is not a situation to be handled on a general patient floor...it is a medical emergency. due to this risk of nms (as well as other potential medication adverse reactions), there is ongoing research in the development of safer pharmaceuticals.

i hope this answered some of your questions.


167 Posts

thanx Thunderwolf, it's great to hear from those with a few notches in their belt. I didn't realize the sxs were so close to serotonin syndrome.

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