Panin 2019: how alcohol medicines, naltrexone included, affect sleep

What they tested

A systematic review gathers every study on a question. This one asked how the four approved alcohol medicines, disulfiram, acamprosate, naltrexone and nalmefene, affect sleep. The authors searched five databases, rated each study's quality and risk of bias, and pooled sleep outcomes in a meta-analysis.

Of the 26 studies included, only three focused on sleep as a main outcome. The rest reported sleep problems among side effects, based on what people said.

What they found

The two drugs that act on opioid receptors, naltrexone and nalmefene, mostly had a harmful effect on sleep, with more insomnia or sleepiness than placebo, though not always significantly.

The meta-analysis confirmed significantly increased somnolence and insomnia in people taking naltrexone compared with placebo.

Acamprosate showed little or no effect on self-reported sleep but improved sleep continuity and structure on polysomnography, an overnight sleep test. The only disulfiram study showed less REM sleep.

The authors suggest acamprosate may be a better fit for people with alcohol use disorder who report sleep problems.

Limits

• Most of the sleep data came from side-effect reports, not sleep measurements.
• Only three studies looked at sleep as a main outcome, and only two used objective sleep tests.
• The abstract says the naltrexone effects were significant but doesn't give their size.

What it means if you're considering naltrexone

Sleep trouble is a real possible side effect of naltrexone: some people sleep worse, others feel drowsy. The evidence comes mostly from people's own reports, and sleep problems are common with heavy drinking and after stopping, so it's hard to know how much comes from the medicine. The authors call for more studies that measure sleep directly.