Two dose levels (190 mg/month and 380 mg/month) of a long-acting, injectable formulation of naltrexone that was developed to increase medication adherence and bioavailability were compared with placebo in a multi-center RCT of 624 participants.19 The median number of binge drinking days during the pre-treatment period was 19.3 days/month, which during the 24-week treatment period declined to 6.0 days/month in the placebo group, 4.5 days/month in the 190-mg group, and 3.1 days/month in the 380-mg group. The decrease in the 380-mg group was significantly greater than in the placebo group,19 leading to its approval by the FDA for treating patients with AUD who are able to abstain from alcohol in an outpatient setting prior to treatment initiation. In a pilot study, 23 male veterans received a 30-day prescription of of oral naltrexone 50 mg and 22 received a single 380-mg intramuscular injection of naltrexone prior to discharge.51 The likelihood of no binge drinking increased in both groups, going from 13.6% during pre-treatment to 75.0% at 45 days post-treatment in the oral naltrexone group and from 13.6% to 77.8% in the
