Naltrexone for Alcohol Use

Naltrexone is the generic name for a medication that can help decrease both the craving for alcohol and the reinforcing “high” one gets while drinking alcohol. 

What is the mechanism of Naltrexone? 
Naltrexone blocks the mu-opioid receptor in the brain. It is thought that this receptor can play a role in the high many people who drink alcohol experience, which is part of what would entice people to consume more and more alcohol at each sitting. 

How long does it take to start working? 
Naltrexone can start working in a few days but will increase in efficacy over a few weeks time. 

What is the dose of Naltrexone used to treat alcohol use disorders? 
50mg/day. 
There is a long acting injectable that is done monthly (vivitrol: 380mg every 4 weeks) for those who have issues with taking daily medications or for those who fear they may purposely stop the capsules. 

What are the side effects to watch for? 
It is usually very well tolerated and most people have no issues. 
In very rare cases there can be liver enzyme increases or what’s called liver toxicity. This usually occurs when doses higher than 50mg are prescribed. If you start to feel physically ill or have nausea, please stop taking the medication and call your primary care doctor.

Other potential but rare side effects listed are: 
GI Upset
Headache
Nausea
Fatigue
Depression
Irritability 
Constipation
High heart rate (tachycardia)