When you or a loved one are looking for a medication to curb alcohol or opioid cravings, the market can feel overwhelming. Naltrexone usually tops the list, but there are several other options that might fit better depending on health status, side‑effect tolerance, and cost. This guide breaks down the science, the numbers, and the real‑world pros and cons so you can decide which drug aligns with your goals.

What Is Naltrexone Hydrochloride?

Naltrexone is an opioid receptor antagonist that blocks the euphoric effects of alcohol and opioids, helping to reduce cravings and relapse risk. It was first approved by the FDA in 1984 for opioid dependence and later for alcohol‑dependence treatment in 1994. The medication is available in oral tablets (50mg) and a once‑monthly injectable depot (380mg) called Vivitrol.

How Naltrexone Works

• Blocks µ‑opioid receptors in the brain, preventing the “high” from alcohol or opioids.
• Reduces dopamine release associated with reward pathways, which lessens cravings.
• Works best when paired with counseling or behavioral therapy.

Clinical trials report a 20‑30% increase in abstinence days compared with placebo, and the injectable form shows slightly better adherence because patients don’t need daily pills.

Key Attributes of Naltrexone

• Dosage: 50mg oral daily; 380mg injectable every 4weeks.
• Efficacy: 30‑40% of patients achieve sustained reduction in drinking; 25‑35% in opioid relapse rates.
• Common Side Effects: nausea, headache, dizziness, fatigue.
• Contraindications: severe liver disease (ALT/AST >3× ULN), acute hepatitis, pregnancy, and opioid use within 7-10days (oral) or 30days (injectable).
• Cost (UK, 2025): £12‑£15 per oral tablet; £250‑£300 per monthly injection.

Popular Alternatives

Below are the main drugs that clinicians consider alongside Naltrexone.

Disulfiram is a drug that causes unpleasant reactions when alcohol is consumed, acting as a deterrent

• Mechanism: Inhibits aldehyde dehydrogenase, leading to acetaldehyde buildup.
• Typical dose: 250mg daily.
• Efficacy: 10‑20% higher abstinence when adherence is high.
• Side effects: metallic taste, skin rash, liver toxicity.
• Contraindications: severe liver disease, severe cardiac disease, pregnancy.

Acamprosate is a calcium salt that stabilizes glutamate neurotransmission, reducing post‑withdrawal cravings

• Mechanism: Modulates NMDA receptors and reduces excitatory neurotransmission.
• Typical dose: 666mg three times daily (total 1998mg).
• Efficacy: 35‑45% increase in abstinent days versus placebo.
• Side effects: diarrhea, abdominal discomfort, insomnia.
• Contraindications: severe renal impairment (creatinine clearance <30mL/min).

Nalmefene is an opioid antagonist with partial agonist activity, approved in Europe for reducing alcohol consumption

• Mechanism: Similar to Naltrexone but with a longer half‑life and partial agonism.
• Typical dose: 18mg as needed (up to once daily).
• Efficacy: 15‑20% reduction in heavy‑drinking days.
• Side effects: nausea, insomnia, dizziness.
• Contraindications: acute opioid use, severe hepatic impairment.

Topiramate is an anticonvulsant that has off‑label use for alcohol dependence by modulating GABA and glutamate

• Mechanism: Enhances GABA‑A activity, inhibits AMPA/kainate receptors.
• Typical dose: 25‑200mg daily, titrated slowly.
• Efficacy: Mixed results; some studies show 20‑30% reduction in drinking.
• Side effects: paresthesia, cognitive slowing, weight loss.
• Contraindications: pregnancy (teratogenic), severe kidney disease.

Comparison Table

Choosing the Right Medication for You

Every drug has a sweet spot. Below is a quick decision guide based on common patient scenarios.

• Patient has liver impairment: Avoid Naltrexone and Disulfiram. Acamprosate (renal‑adjusted) or Topiramate may be safer.
• Patient wants occasional dosing: Nalmefene’s “take when you feel a craving” approach fits social drinkers aiming for harm reduction.
• High risk of non‑adherence: Injectable Naltrexone guarantees monthly coverage; Disulfiram is effective only if the patient never drinks.
• Concurrent opioid use disorder: Naltrexone (after detox) or Topiramate can address both, while Disulfiram and Acamprosate are alcohol‑specific.
• Budget‑conscious: Generic oral Naltrexone and Disulfiram are the cheapest; Topiramate is inexpensive but off‑label.

Practical Tips for Clinicians and Patients

1. Perform baseline liver and renal labs before initiating therapy.
2. Educate patients on the need for abstinence from opioids for at least 7days before starting oral Naltrexone to avoid precipitated withdrawal.
3. Use a medication‑adherence tool (e.g., weekly text reminders) for daily tablets.
4. Combine pharmacotherapy with evidence‑based counseling-Motivational Interviewing or Cognitive‑Behavioral Therapy improves outcomes by ~15%.
5. Monitor side effects at 2‑week and 8‑week visits; adjust dose or switch agents if intolerable.

Potential Pitfalls and How to Avoid Them

• Premature discontinuation: Some patients stop after a few weeks because they don’t feel immediate effects. Set realistic expectations - reduction in cravings may take 2‑4weeks.
• Drug‑drug interactions: Naltrexone is metabolized minimally by the liver but can interact with opioid analgesics; Disulfiram can potentiate hepatotoxicity with certain antidepressants.
• Misuse of deterrent drugs: Patients on Disulfiram may attempt to “test” the reaction by drinking small amounts, risking severe reactions. Close monitoring and counseling are essential.
• Renal dosing errors: Acamprosate requires dose reduction in CKD; failure to adjust can lead to accumulation and GI upset.

Next Steps for Readers

If you’re considering medication‑assisted treatment, start by consulting a GP or addiction specialist. Bring this comparison sheet, ask about baseline labs, and discuss which drug aligns with your health profile and lifestyle. Remember, medication works best when paired with ongoing support.

Frequently Asked Questions

Can I take Naltrexone and Acamprosate together?

Yes, combining Naltrexone (opioid antagonist) with Acamprosate (glutamate modulator) is sometimes prescribed for patients who need both craving reduction and post‑withdrawal stabilization. There are no known pharmacokinetic interactions, but monitor for additive side‑effects like fatigue or GI upset.

Why did my doctor suggest an injectable instead of a pill?

Injectable Naltrexone (Vivitrol) eliminates the need for daily adherence, which is a major cause of treatment failure. It also reduces the risk of missed doses leading to relapse. The trade‑off is a higher upfront cost and the requirement to be opioid‑free for at least 30days before the first injection.

Is Disulfiram still recommended in 2025?

Disulfiram remains an option, especially for patients who prefer a strong deterrent and are highly motivated to stay sober. Guidelines now advise it only after thorough liver testing and when patients understand the severe reaction risk.

Can I use Nalmefene if I’m also on antidepressants?

Nalmefene has no direct interaction with most antidepressants, but both can cause insomnia or dizziness. Discuss any mood‑altering drugs with your prescriber to fine‑tune the schedule.

What should I do if I experience nausea on Naltrexone?

Take the tablet with food, split the dose (if using oral), or switch to the injectable form, which tends to have fewer GI side effects. If nausea persists beyond a week, contact your clinician for a possible dosage adjustment.