Diagnostic Criteria for Neuroleptic Malignant Syndrome.
The information below is based on information from the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Washington, DC, American Psychiatric Association, 1994.

A. The development of severe muscle rigidity and elevated temperature associated with the use of antipsychotic medication.

B. Two (or more) of the following:

1. diaphoresis
2. dysphagia
3. tremor
4. incontinence
5. changes in level of consciousness ranging from confusion to coma
6. mutism
7. tachycardia
8. elevated or labile blood pressure
9. leucocytosis
10. laboratory evidence of muscle injury (e.g., elevated CK)

C. The symptoms in Criteria A and B are not due to another substance (e.g., phencyclidine) or a neurological or other general medical condition (e.g., viral encephalitis).

D. The symptoms in Criteria A and B are not better accounted for by a mental disorder (e.g., Mood Disorder with Catatonic Features).