Isoniazid-associated rhabdomyolysis.

We report the occurrence of rhabdomyolysis and hepatitis in a 17-year-old girl after the ingestion of up to 10.8 g of isoniazid. The initial isoniazid concentration in the blood was 1,230 mmol/L. There were no findings indicating the ingestion of other substances known to be associated with rhabdomyolysis. In addition to rhabdomyolysis (peak creatine phosphokinase 88,000 U/L), the patient had a significant elevation of her liver enzymes (peak aspartate aminotransferase 1,980 U/L). She recovered completely without evidence of liver or renal damage. Rhabdomyolysis and isoniazid-induced hepatitis are complications that should be considered when caring for patients with acute isoniazid ingestion.