Key Differences Explained
Acamprosate and naltrexone are both FDA-approved medications for alcohol use disorder, but they work through completely different mechanisms and serve different clinical purposes.
Acamprosate (Campral) works by restoring the balance of brain chemicals (GABA and glutamate) disrupted by chronic alcohol use. It's most effective for people who have already stopped drinking and want to maintain abstinence. It reduces the post-acute withdrawal symptoms — anxiety, insomnia, restlessness — that drive early relapse.
Naltrexone blocks opioid receptors in the brain, reducing the pleasurable effects of alcohol. It can be taken as a daily pill (ReVia) or monthly injection (Vivitrol). Unlike acamprosate, naltrexone can be started while you're still drinking — it reduces heavy drinking days and cravings.
Can You Take Both?
Yes. The COMBINE study (the largest alcohol medication trial ever) found that combining naltrexone with behavioral therapy produced the best outcomes. Adding acamprosate didn't significantly improve results in this US study, though European trials showed stronger acamprosate effects. Some clinicians prescribe both for patients with severe alcohol dependence.
What About Disulfiram?
A third option, disulfiram (Antabuse), works through aversion — making you violently ill if you drink. It's effective for highly motivated patients but has compliance challenges.