The Sinclair Method is a medication-assisted treatment approach for alcohol use disorder that uses the drug naltrexone to block the pleasurable effects of alcohol. The length of time it takes to complete the Sinclair Method varies from person to person, as it depends on individual factors such as the severity of the alcohol use disorder and how long the person has been drinking.

Some people may see results within a few weeks of starting the Sinclair Method, while others may take several months. The goal of the Sinclair Method is not necessarily abstinence from alcohol, but rather a reduction in the amount of alcohol consumed and a decrease in cravings. It is important for individuals to continue taking naltrexone as prescribed by a healthcare professional, even if they have achieved a reduction in alcohol consumption, as discontinuing the medication can increase the risk of relapse.