Rhabdomyolysis associated with naltrexone

OBJECTIVE: To report a possible association between naltrexone therapy and the development of rhabdomyolysis in one patient. CASE SUMMARY: A 28-year-old white man in good physical health was started on naltrexone 50 mg/d for inpatient treatment of alcohol dependence and depression. A routine serum chemistry panel obtained on day 9 of naltrexone therapy showed marked new elevations in creatine kinase and aspartate aminotransferase. The patient remained asymptomatic and did not develop renal insufficiency. The serum enzyme concentrations returned to normal within eight days of naltrexone discontinuation. DISCUSSION: Rhabdomyolysis has not been previously reported to occur in patients during treatment with naltrexone. Alcoholism may result in a reversible acute muscle syndrome, but our patient did not fit the appropriate clinical profile for such a syndrome. Additionally, the other prescribed medications could not be implicated as possible causative agents. CONCLUSIONS: This case report illustrates a possible association between naltrexone therapy and rhabdomyolysis.