Neuroleptic malignant syndrome: literature review

Algirdas Musneckis

1

, Kornelija Varkalaitė

2

, Gabija Tamulionytė

2

1

Lithuanian University of Health Sciences Kaunas Hospital, Department of Psychiatry, Kaunas, Lithuania

2

Materials and methods. PubMed and UpToDate were searched using terms “neuroleptic malignant syndrome”

in combination with “diagnosis”, “treatment” and “complications”. Articles were included if they were in English,

no more than 10 years old, and included adults. Articles were excluded if they did not meet the inclusion criteria

and were not relevant.

Results. The risk for NMS increases for males, patients in their early to middle forties, patients using haloperidol

or flupentixol and patients receiving polypharmacological treatment. NMS laboratory findings are nonspecific

while SPECT may be a prospective diagnostic tool. Treatment of NMS is assigned individually and relies on the

severity of the case. Patients can be treated with medications or electroconvulsive therapy, and receive intensive

care unit monitoring. Acute respiratory failure can be the strongest independent mortality predictor.

Conclusions. Diagnosis of NMS can be complicated, once the condition is suspected patients should receive

Neuroleptic malignant syndrome (NMS) is a rare

and potentially lethal neurological condition

(1,2). It usually presents with fever (˃38

rigor, altered mental status and other

neurological symptoms (3). NMS is a known

adverse reaction to antipsychotic drugs, but it

analyze the most recent data on diagnostics,

treatment and complications of NMS.

The search was conducted in the PubMed

database and the UpToDate clinical database.

The terms used for the search were “neuroleptic

malignant syndrome” in combination with

“diagnosis”, “treatment”, “complications”.

Articles were included in the review if they were

As NMS can be a fatal condition it is important

to suspect and diagnose it as soon as possible.

The incidence of NMS seems to be higher

among male patients (3,5,6). The mean age of

onset ranges from early to middle forties (5,6).

Antipsychotic drugs are the main cause of NMS,

however, a difference between the ability to

hypocalcemia), increased lactate dehydrogenase

and metabolic acidosis all of which are common,

but nonspecific findings during NMS (6,12,13).

Serum creatine kinase can range from 572–

220,000 IU/L (6). SPECT may be a prospective

diagnostic tool for NMS as FP/CIT SPECT has

shown either reduced or absent uptake in the

Treatment of patients with NMS is based on

clinical symptoms (12). The most important step

is the removal of the causing agent (3).

Psychotropic drugs such as lithium,

anticholinergic and serotonergic agents should

also be removed. Specific medical treatment

recommendations mostly rely on clinical

experience. Medications are most commonly

used in severe or moderate NMS. Patients

receive dantrolene, bromocriptine and

lowering with cool blankets, ice water and/or ice

packs, blood pressure control (nitroprusside can

be effective as it also causes cooling through

vasodilation of the skin vessels), heparin or low

molecular weight heparin to prevent deep

venous thrombosis. Benzodiazepines may also

be used for agitation control (12). Electro-

convulsive therapy (ECT) might be another

method to treat NMS, although randomized

controlled trials are lacking (10). ECT is mostly

approaches as well as electroconvulsive therapy.

Acute respiratory failure is a complication that

can be a strong mortality predictor.

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