Quetiapine-induced neuroleptic malignant syndrome in a patient with traumatic brain injury: a case report

Neuroleptic malignant syndrome (NMS) is a rare but life-threatening complication of antipsychotic therapy that can be mistaken for paroxysmal sympathetic hyperactivity (PSH) in traumatic brain injury (TBI), particularly when creatine kinase elevation is modest or when symptoms fluctuate. We report the case of a 54-year-old man with severe TBI who developed episodic PSH-like manifestations during recovery. Initial PSH-directed treatment was effective. However, after reintroduction of high-dose quetiapine, he began to exhibit recurrent manifestations resembling PSH that were refractory to treatment. Although the fluctuating clinical course and only modest creatine kinase (CK) elevation initially favored PSH, the clear temporal association with quetiapine reexposure supported a diagnosis of NMS. Discontinuation of quetiapine and initiation of NMS-targeted management resulted in rapid clinical improvement. This case highlights the diagnostic challenge of distinguishing NMS from PSH in critically ill patients with TBI and underscores the importance of cautious reintroduction and gradual titration of antipsychotics, as well as early consideration of NMS even in the absence of marked CK elevation.