The safety profile of naltrexone in the treatment of alcoholism. Results from a multicenter usage study. The Naltrexone Usage Study Group.

BACKGROUND: Naltrexone hydrochloride is the first medication approved in the United States for the treatment of alcohol dependence in almost 50 years. This study was designed to collect safety data in a setting that reflected the expected clinical use of naltrexone.
METHODS: This was a 12-week, nonrandomized, open-label usage study conducted in 40 alcoholism treatment centers throughout the United States, including free-standing alcoholism treatment programs, university clinics, Veterans Administration hospitals, and office-based primary care practices. Eligible patients were assigned, at the investigators' discretion, to a naltrexone treatment group or to a reference group that did not receive study medication. At study entry, patients must have been abstinent from alcohol for 1 to 6 weeks and enrolled in a psychosocial treatment program for alcoholism. Patients often underrepresented in controlled clinical trials, including women and patients with comorbid medical and psychiatric illness, were eligible. Patients with polysubstance abuse or infection with the human immunodeficiency virus were not excluded.
RESULTS: Of 865 patients enrolled, 570 received naltrexone and 295 were in a reference group. The most common new-onset adverse clinical events in the naltrexone group were nausea (9.8%) and headache (6.6%). Naltrexone was discontinued in 15.0% of patients because of adverse events, most frequently nausea. The results of liver function tests in the naltrexone group were similar to those in the reference group. No death occurred during the study.
CONCLUSIONS: This is the largest study to date describing the safety of naltrexone in a heterogeneous population of persons with alcoholism. No new safety concerns were identified.