An uncommonly recognized cause of rhabdomyolysis after quetiapine intoxication

Antipsychotics can cause acute rhabdomyolysis (RM) as part of a neuroleptic malignant syndrome or via a direct toxic effect on myocytes. Such a serious adverse effect has been rarely linked to quetiapine treatment. This report highlights a different pathophysiology of RM after quetiapine overdosing with suicidal intent. The 44-year-old patient had schizophrenia and took 9000 mg, 10 times his daily dosage. He became somnolent and later unconscious. After lying for 14 hours on a firm mattress probably motionless, he was difficult to arouse next morning and could hardly walk. In the emergency department (ED), brown urine and a creatinine kinase (CK) of 30 660 U/L were detected. Rhabdomyolysis was treated successfully with plasma expansion. A compartment syndrome led to bilateral peroneal paresis. A direct toxic effect of quetiapine on myocytes as claimed in the past is unlikely because, after reexposure to quetiapine 3 months later, CK remained normal. It is recommended that every patient who overdosed on quetiapine should be thoroughly assessed in ED including measurement of CK to detect RM due to long immobility early and avoid acute renal failure.