Which of the following statements about naltrexone in alcohol use disorder (AUD) is most accurate?

• A Naltrexone reduces the rewarding effects of alcohol by blocking µ-opioid receptors and is most effective in patients with family history of alcoholism or OPRM1 A118G variant ✓
• B Naltrexone must be given only in completely abstinent patients as it causes severe withdrawal if given to active drinkers
• C Naltrexone should always be combined with disulfiram for maximum efficacy
• D Naltrexone is contraindicated in patients on buprenorphine for opioid use disorder

Explanation

Naltrexone reduces alcohol craving and the rewarding 'high' from alcohol by blocking mu-opioid receptors (alcohol activates the endogenous opioid system). Pharmacogenomic evidence shows patients with the OPRM1 A118G (Asp40) variant respond better to naltrexone. Naltrexone does NOT cause precipitation of alcohol withdrawal — this is the disulfiram reaction concept. Naltrexone is safe in active drinkers (though hepatotoxicity risk requires LFT monitoring). Combining naltrexone with disulfiram is not evidence-based. Naltrexone is indeed contraindicated in patients currently on opioids (including buprenorphine) as it would precipitate opioid withdrawal.

Reference: Kaplan & Sadock's Synopsis of Psychiatry, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.