Naltrexone, acamprosate favoured in meta-analysis of alcohol use disorder medications

Oral naltrexone and acamprosate are associated with improved outcomes in individuals with alcohol use disorder and are supported as first-line pharmacotherapies in a meta-analysis.

Researchers conducted a systematic review of randomized clinical trials and prospective cohort studies of therapies for alcohol use disorder. The inclusion criteria were an intervention duration of at least 12 weeks and assessment of health outcomes or harms.

Multiple online databases were searched for relevant studies. A total of 118 clinical trials that involved 20,976 participants met the eligibility criteria and were included in the meta-analysis. Each trial was evaluated for the risk of bias and graded for the strength of evidence.

The primary endpoint was alcohol consumption. Secondary endpoints included motor vehicle crashes, injuries, quality of life, function, mortality, and harms. Random-effects models were used in the meta-analyses, and numbers needed to treat were calculated for medications with at least moderate strength of evidence for benefit.

Pooled data showed that the numbers needed to treat to prevent a single person from returning to any drinking were 11 (95 percent confidence interval [CI], 1–32) for acamprosate and 18 (95 percent CI, 4–32) for oral naltrexone at a dose of 50 mg/d.

Compared with placebo, oral naltrexone treatment led to decreased likelihood of returning to heavy drinking, with a number needed to treat of 11 (95 percent CI, 5-41). Meanwhile, injectable naltrexone was associated with fewer drinking days over the 30-day treatment period (weighted mean difference, −4.99 days, 95 percent CI, −9.49 to −0.49).

In terms of safety, gastrointestinal distress was the most frequent adverse effect. Specifically, diarrhoea occurred commonly among people treated with acamprosate versus placebo (risk ratio [RR], 1.58, 95 percent CI, 1.27–1.97). Among people treated with naltrexone, on the other hand, nausea (RR, 1.73, 95 percent CI, 1.51–1.98) and vomiting (RR, 1.53, 95 percent CI, 1.23–1.91) were mostly observed.