Three Episodes of Neuroleptic Malignant Syndrome With Risperidone: A Case Report and Literature Review.

Neuroleptic malignant syndrome (NMS) is an idiosyncratic and life-threatening side effect that usually occurs in response to dopamine receptor antagonist medications. Despite increased awareness, the diagnosis of NMS remains challenging due to its wide differential diagnoses, which can lead to delayed treatment and increased mortality or premature reinitiation of the causative agent, culminating in recurrent NMS, a phenomenon with limited reports. This case presents a patient who experienced three episodes of NMS within 1 year, all triggered by risperidone. A 58-year-old male patient with schizophrenia presented to the emergency department of a university hospital in Northern Iran, due to decreased consciousness, fever, and rigidity. Initial laboratory results showed elevated creatine phosphokinase (CPK) at 14,949 U/L. He had two previous episodes of rhabdomyolysis and hospitalization in the past year. Review of prior hospital records indicated treatment for rhabdomyolysis with symptoms consistent with NMS, without making this diagnosis. In any patient treated with dopaminergic drugs who suffer from mental status changes, muscle stiffness, high fever, and dysautonomia, especially who have complications such as rhabdomyolysis, kidney failure, seizures, leukocytosis, and increased CPK and lactate dehydrogenase (LDH), the possibility of NMS should be considered.