Case of Neuroleptic Malignant Syndrome Following Antipsychotic Overdose: A Case of Survival

Abstract

Background: Neuroleptic Malignant Syndrome (NMS) is a rare but potentially fatal adverse reaction to dopamine receptor–blocking agents. It is characterized by hyperthermia, generalized rigidity, altered sensorium, autonomic instability, and elevated serum creatine kinase (CK). Antipsychotic overdosage is a recognized precipitating factor, and early diagnosis is critical for survival.

Methods: This is a descriptive single-patient case report. Clinical evaluation, laboratory investigations including serum CK and liver enzymes, and neuroimaging were used to establish the diagnosis. Management involved immediate discontinuation of antipsychotics, intensive care monitoring, aggressive supportive treatment, and dopaminergic agents.

Case Discussion: A 45-year-old male with schizophrenia presented with five days of high-grade fever, severe generalized “lead-pipe” rigidity, altered consciousness, and poor oral intake following excessive ingestion of risperidone and olanzapine. Examination revealed hyperthermia, tachycardia, and labile blood pressure. Investigations showed leukocytosis, markedly elevated CK, and raised liver enzymes; MRI brain was normal. The patient was managed in the ICU with active cooling, intravenous hydration, electrolyte correction, bromocriptine, and amantadine. Gradual clinical and biochemical improvement occurred over one month. Subsequent cautious antipsychotic rechallenge with low-dose clozapine and amisulpride was well tolerated.

Conclusion: Early recognition, prompt withdrawal of offending agents, intensive supportive care, and multidisciplinary management are essential for survival in NMS. Carefully monitored antipsychotic rechallenge can be safely undertaken after complete recovery.