Buprenorphine-naloxone treatment in opioid dependence and risk of liver enzyme elevation: results from a 12-month observational study.

BACKGROUND: Some case series mention possible liver toxicity in opioid-dependent patients under buprenorphine treatment. METHODS: This 12-month prospective observational follow-up study in opioid-dependent patients under buprenorphine-naloxone treatment assessed outcome and safety issues. At baseline, 337 eligible datasets were available; 181 patients completed the 12-month study. Liver enzymes were tested at baseline and after 12, 24, and 52 weeks' treatment. RESULTS: One to two percent of patients showed mostly discrete elevations of liver enzymes, but no patient met the criteria for drug-induced liver injury. No serious liver-related adverse events occurred, but two non-serious cases of liver enzyme increase were recorded. No patient dropped out of treatment for liver-related disorders. CONCLUSION: This study is in line with some recent studies and provides further evidence that buprenorphine-naloxone is relatively safe with respect to liver injury.