acamprosate vs naltrexone
Side-by-side comparison of acamprosate and naltrexone Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
The pharmacokinetics of acamprosate are not affected by alcohol, diazepam, or disulfiram, and clinically important interactions between naltrexone and acamprosate were not observed [ see Clinical Pharmacology (12.3) ].
Recommendation: You can take these medicines together as no major issues have been found.
Campral
Vivitrol, ReVia
Acamprosate is a medicine that can help you stay away from alcohol if you are alcohol-dependent and have already stopped drinking. It should be used with counseling and support.
Naltrexone is a medicine that can help treat alcohol and opioid dependence. It works by blocking the effects of opioids in your body.
Acamprosate helps people who are alcohol-dependent to not drink alcohol. You must have already stopped drinking before you start taking acamprosate. This medicine works best when it is part of a complete treatment plan that includes counseling and support.
Naltrexone is used to treat alcohol dependence and to block the effects of opioid drugs. It is important to use naltrexone as part of a complete treatment plan. This plan should include counseling and support to help you stay sober or opioid-free.
Acamprosate is similar to a natural substance in your brain. It is thought to work by helping to restore the normal balance of brain activity that is changed by long-term alcohol use. This can reduce your craving for alcohol.
Naltrexone blocks the effects of opioids by attaching to opioid receptors in the brain. This prevents opioids from having their usual effects, like pain relief or feelings of euphoria. By blocking these effects, naltrexone can help reduce cravings for alcohol or opioids.
- • Accidental injury
- • Weakness
- • Pain
- • Loss of appetite
- • Diarrhea
- • Nausea
- • Headache
- • Fatigue
- • Insomnia
- • Anxiety
- Low blood pressure 14
- Weakness 13
- Condition worsened 13
- Using the medicine for something it is not approved for 13
- Sudden kidney damage 12
- Reaction at the injection site 4,407
- Pain at the injection site 3,111
- Feeling sick to your stomach 2,094
- Alcohol addiction 1,942
- Lump at the injection site 1,895
Acamprosate may increase the risk of suicidal thoughts or actions. Your doctor should watch you for depression or suicidal thoughts. Tell your doctor right away if you have any new or worsening symptoms of depression or suicidal thoughts.
Naltrexone can cause serious withdrawal symptoms if you are still using opioids. Make sure you are opioid-free for at least 7 to 10 days before starting naltrexone. If you experience severe withdrawal symptoms, seek medical help right away.
Acamprosate may harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if acamprosate passes into breast milk. Talk to your doctor if you are breastfeeding.
It is not known if naltrexone is safe to use during pregnancy. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if naltrexone passes into breast milk, so talk to your doctor if you are breastfeeding.
How to Read This acamprosate vs naltrexone Comparison
acamprosate is classified in the GABA Analog (Alcohol Dependence) drug class, while naltrexone sits within the Opioid Antagonist class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, acamprosate has 65 submissions while naltrexone has 13,449. Those figures reflect cumulative reporting volume — not per-patient risk — so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to these two drugs do not significantly change how the other works in your body.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between acamprosate and naltrexone — always consult your physician or pharmacist first.
Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.