Neuroleptic Malignant Syndrome Induced by Clozapine: A Case Report and Discussion

Objective: Neuroleptic malignant syndrome (NMS) is a rare, but life-threatening condition associated with the use of antipsychotics. Although NMS is mainly associated with typical antipsychotics, it can also be induced by atypical antipsychotics. In this paper, we report a case of NMS associated with clozapine use and describe the classic and atypical manifestations of NMS. The case and discussion highlight the importance of considering NMS as part of the differential diagnosis for any patient using neuroleptics.

Case: This case was about a 52-year-old female suffering from pneumonia, who was diagnosed as having NMS after a dosage increase of clozapine. NMS is a rare but serious adverse reaction to an antipsychotic drug. It is essentially characterized by hyperthermia, and muscle rigidity, which may be accompanied by other extra pyramidal effects (EPS), autonomic instability and mental status changes. Laboratory examinations showed significantly higher creatine kinase. A typical treatment usually involves supportive medication and an immediate withdrawal of the antipsychotic drug.

Conclusion: Incomplete or extraordinary NMS cases have been reported due to clozapine. However, this case was remarkably associated with the complete and typical presentation of NMS. Given the routine and regular writing of prescriptions of neuroleptics by physicians in a variety of medical disciplines, physicians need to recognize and appropriately manage NMS.