Substance guides

Naltrexone for alcohol: How it reduces cravings

Published November 8, 2025 · 7 min read · Updated April 2026
Reviewed for accuracy by licensed clinical professionals.

Naltrexone is one of three FDA-approved medications for alcohol use disorder and one of the most effective tools available for reducing drinking.

How it works

Naltrexone blocks opioid receptors, which are involved in the pleasurable effects of alcohol. With naltrexone on board, alcohol produces less pleasure, reducing the reinforcement that drives continued drinking. Over time, this weakens the learned association between alcohol and reward.

Dosing options

Daily oral naltrexone (50mg tablet): taken every day regardless of drinking. The Sinclair Method: naltrexone taken specifically 1 hour before drinking (targeted pharmacological extinction). Vivitrol injection: 380mg monthly injection for those who prefer not to take daily pills or have adherence challenges.

The Sinclair Method

TSM uses naltrexone only before drinking sessions, allowing the brain to gradually unlearn the alcohol-reward association through pharmacological extinction. Studies show 78% reduction in drinking over 3-4 months. Some people achieve complete abstinence; others achieve controlled, non-problematic drinking.

Side effects

Nausea (usually resolves within a week), headache, fatigue, and reduced appetite. Starting at half dose for the first week reduces nausea. Cannot be taken with opioid medications.

Authoritative sources

This article references guidelines from: NIDA · SAMHSA · CDC

Frequently asked questions

Does naltrexone work for alcoholism?
Yes. Naltrexone reduces heavy drinking days by 25-36% and is one of the most effective medications for AUD.
What is the Sinclair Method?
Taking naltrexone 1 hour before drinking to block the reward response. Studies show 78% reduction in drinking over 3-4 months.
Can I drink on naltrexone?
Naltrexone does not prevent drinking. It reduces the pleasure from alcohol, gradually weakening the desire to drink.

Disclaimer: Informational only. Not medical advice. SAMHSA: 1-800-662-4357.