Among alcohol-use interventions, which statement correctly describes the mechanisms of naltrexone, acamprosate, and disulfiram?

• A. The three drugs share identical mechanisms.
• B. Naltrexone blocks norepinephrine; acamprosate modulates dopamine; disulfiram inhibits serotonin synthesis.
• C. Naltrexone reduces rewarding effects; acamprosate modulates glutamatergic transmission to reduce cravings; disulfiram inhibits aldehyde dehydrogenase to produce aversive effects.
• D. There is no pharmacologic treatment for alcohol use disorder.

Answer: (C)

Different medications for alcohol use disorder act through distinct mechanisms.

Naltrexone works as an opioid receptor antagonist, blunting the rewarding and reinforcing effects of alcohol. By blocking endogenous opioid signaling, it reduces the pleasurable aspects of drinking and helps lower relapse risk.

Acamprosate helps stabilize glutamatergic neurotransmission, especially during withdrawal, which dampens craving and supports abstinence by reducing the brain’s hyperglutamergic state.

Disulfiram inhibits the enzyme aldehyde dehydrogenase, so if alcohol is consumed, acetaldehyde accumulates and produces aversive symptoms (flushing, tachycardia, nausea). This creates a deterrent effect against drinking.

Because these drugs have different targets—reward pathways, glutamatergic balance, and aversive conditioning—the statement that they share identical mechanisms is incorrect, while the described mechanisms align with current pharmacologic actions.