Which statement describes a drawback of monthly injectable naltrexone?

• A. Alcohol Should Not Be Ingested Prior To Starting Or Will Cause Precipitated Withdrawal
• B. It Is Incompatible With All Opioids
• C. It Has Significant Renal Dosing Requirements
• D. It Is Inexpensive And Widely Available

Answer: (B)

Long-acting naltrexone is an opioid receptor antagonist, meaning it blocks the effects of opioids at the receptors. The big drawback is that it is incompatible with any opioid use. If a person takes an opioid while the antagonist is active, they won’t get the usual opioid effects and can experience precipitated withdrawal because the blocker displaces the opioid from the receptors. That blockade lasts about a month, which means patients must be opioid-free before starting and must stay abstinent while on treatment. This limitation is a fundamental reason clinicians use naltrexone only after detoxification and choose it when the goal is complete opioid blockade rather than allowing ongoing opioid use for pain relief or relapse management.