Naltrexone vs Acamprosate and Disulfiram
Naltrexone, acamprosate, and disulfiram have different goals, contraindications, and evidence. There is no universal best medicine.

Key takeaways
- Naltrexone and acamprosate have different strengths; treatment goals and health history matter.
- Standard acamprosate dosing is 666 mg three times daily in adults with normal renal function—not 666 mg total per day.
- Acamprosate is contraindicated in severe renal impairment and is not primarily a liver-metabolised medicine.
- Naltrexone requires attention to current opioid use and liver status.
- Disulfiram causes a potentially serious reaction with alcohol and requires careful education and selection.
Medication comparison
| Naltrexone | Acamprosate | Disulfiram | |
|---|---|---|---|
| Common goal | Reduce heavy drinking or support abstinence | Maintain abstinence after withdrawal | Create a deterrent to drinking |
| Typical adult schedule | Often 50 mg daily; follow the product label and clinician plan | 666 mg three times daily with normal renal function; lower dose in moderate renal impairment | Individualized daily dosing under clinician supervision |
| Major organ consideration | Liver history and symptoms; current opioids are critical | Kidney function; contraindicated in severe renal impairment | Liver and cardiovascular risks among several contraindications |
| If alcohol is consumed | No disulfiram-like reaction; impairment and alcohol toxicity still occur | No direct deterrent reaction | Acetaldehyde reaction can be severe |
| Evidence position | Common first-line option | Common first-line option | Selected patients; adherence and supervision matter |
The choice is not just an efficacy ranking
A medicine can be effective in trials but unsuitable for a particular person. Clinicians also consider:
- current treatment goal;
- recent opioid use or expected opioid pain treatment;
- kidney and liver function;
- pregnancy and breastfeeding;
- adherence pattern and dosing burden;
- concurrent medicines and mental health;
- availability, registration, and cost in the local market.
Country availability needs product-level verification
Availability should not be inferred from an educational medicine page or from another country. Our current checks found strong standalone-naltrexone product evidence in Australia, New Zealand, South Africa, the UK, US, and Canada. In Singapore and the UAE, current public records more clearly establish the naltrexone/bupropion combination product than standalone 50 mg naltrexone.
Acamprosate and disulfiram should be checked by exact product and country rather than described as broadly “available” or “unavailable.”
Primary sources
- DailyMed: acamprosate prescribing information
Dosing and renal contraindication.
- DailyMed: naltrexone tablet prescribing information
Opioid and hepatic warnings.
- NICE CG115 recommendations
Positions acamprosate and oral naltrexone after assisted withdrawal.