Acamprosate Does Have Efficacy for Alcohol Dependence

Some high-profile negative trials have raised questions regarding the efficacy of acamprosate for treating alcohol dependence. Cochrane Collaboration investigators systematically searched for double-blind randomized placebo-controlled trials of acamprosate and identified 24 that assessed drinking outcomes in 6915 patients with alcohol dependence. All patients in the included studies received concurrent psychosocial treatment. Acamprosate treatment varied from 8 weeks to 1 year, with most patients receiving treatment for 6 months. The majority of studies required 3–7 days of abstinence before starting medication; 2 required 12–14 days, and, in 1 study, half the participants were drinking when they began medication. Most studies took place in Europe; 2 occurred in the US, and 3 occurred outside Europe.

• Compared with placebo, acamprosate significantly increased self-reported continuous abstinence (25% versus 17%) (relative risk of return to any drinking, 0.82) and cumulative days of abstinence (11-day increase) but had no effect on heavy drinking or serum gamma glutamyltransferase results.

• The only side effect more common with acamprosate than placebo was diarrhea (11% higher risk).

• Three studies comparing acamprosate and naltrexone found no significant differences when comparing or combining the 2 medications.

• Studies outside Europe found no significant effects for acamprosate.

Comments:

The evidence supports acamprosate’s efficacy for treating alcohol dependence, although, unlike naltrexone, it does not appear to reduce heavy drinking. The reason studies outside Europe were negative overall could be that 1 out of 5 did not require abstinence before treatment initiation, and 3 others were small. Despite modest efficacy, acamprosate should remain a treatment option because alcohol dependence is serious and other treatments have shown limited success.

Richard Saitz MD, MPH

Reference:

Rösner S, Hackl-Herrwerth A, Leucht S, et al. Acamprosate for alcohol dependence. Cochrane Database Sys Rev. 2010;9:CD004332.