Naltrexone for alcohol: How the Sinclair Method works

The Sinclair Method (TSM) is an approach to alcohol use disorder that challenges the traditional abstinence model. Instead of stopping drinking and using willpower to stay stopped, TSM involves taking naltrexone one hour before drinking — and then drinking. The mechanism behind this approach is called pharmacological extinction.

How it works

Naltrexone blocks opioid receptors in the brain. When you drink alcohol, endorphins are released that bind to these receptors, producing the pleasurable, rewarding feeling that reinforces the drinking habit. When naltrexone is blocking those receptors, you can still drink — but the reward is diminished or absent. Over time (typically 3-6 months of consistent compliance), the brain gradually unlearns the association between alcohol and reward. Drinking becomes less compelling, less urgent, and many people naturally reduce consumption or stop entirely — not through willpower, but through neurological extinction of the learned reward response.

What the evidence shows

The original research by Dr. David Sinclair in Finland showed a 78% success rate (defined as either abstinence or moderate, controlled drinking) over a 3-4 month period. Multiple subsequent studies have confirmed naltrexone's effectiveness for reducing heavy drinking days and overall alcohol consumption. The Sinclair Method specifically (naltrexone taken only before drinking, not daily) has strong clinical support but is less widely practiced in the US than daily naltrexone, partly because it contradicts the abstinence framework that dominates American addiction treatment.

How to use it

The protocol is straightforward: take 50mg of naltrexone exactly one hour before your first drink. Every time you drink, you take naltrexone first. Every time. Skipping the naltrexone before drinking allows the reward response to re-establish. On days you do not drink, you do not take naltrexone. Keep a drinking log to track your consumption over time — most people see gradual, measurable reduction over weeks to months.

Finding a prescriber

Many addiction medicine physicians are familiar with TSM. Telehealth services like Ria Health, Oar Health, and Monument specialize in TSM. Your primary care physician can prescribe naltrexone — share the research if they are unfamiliar with the approach. Naltrexone is a generic medication and is generally affordable, even without insurance.

Treatment facilities

Authoritative sources

This article references guidelines from: NIDA · SAMHSA · CDC · FDA · ASAM

Frequently asked questions

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