Acamprosate (Campral)

FDA Approved 2004

Reviewed by the HeyPsych Medical Review Board

Board-certified psychiatrists and mental health professionals

Published November 24, 2025•Updated November 28, 2025•Reviewed November 24, 2025

Clinical summary for Acamprosate (Campral): Acamprosate is a medicine for people who have already stopped drinking and want help staying sober. It can lessen the physical drive to drink and make it easier to maintain abstinence over time.

What It's Used For

Acamprosate is used to help people with alcohol use disorder stay abstinent after they have already stopped drinking. It is not used to manage withdrawal or to help someone cut down while still drinking heavily.

Primary Indications

alcohol use disorder

Patient-Friendly Explanation

This medication is meant for people who have already gone through detox and stopped drinking. It is used to help them stay alcohol-free and is not useful if someone is still drinking regularly.

What People Feel

Everyone responds differently, but these are common experiences people report while taking acamprosate after they stop drinking:

Cravings and Urges

"The urge to drink is still there sometimes, but it feels more distant and easier to say no."

Onset and Duration of Benefit

Clinical benefit generally emerges within about 5–8 days of starting treatment, with effects maintained as long as therapy continues and abstinence is supported.

Clinical benefit often begins within 5–8 days after starting acamprosate.

Full effect may take several weeks of sustained abstinence and regular dosing.

Benefits are maintained only while the medication is continued and alcohol use remains minimal or absent.

How Well It Works

Continuous abstinence rate at 6 months

vs 23.4% for placebo

Active

36%

Placebo

23.4% for placebo

A meta-analysis of randomized clinical trials found that 36% of patients treated with acamprosate maintained continuous abstinence at 6 months, compared with 23.4% of those receiving placebo. The benefit is modest but clinically important when combined with behavioral treatment.

Warnings & Precautions

Monitor mood closely, especially in early recovery, and avoid using acamprosate as a substitute for comprehensive alcohol use disorder treatment.

→Let your clinician know right away if you feel more depressed, hopeless, or have thoughts of harming yourself.
→You need to be abstinent before starting acamprosate; this medicine does not treat withdrawal and will not help you safely stop alcohol on your own.
→If you slip and drink, do not stop the medication on your own—talk with your treatment team. Acamprosate is often continued to support getting back to sobriety.

Side Effects

The most common side effect is diarrhea, which is usually mild to moderate and often improves over time. Mood changes and sleep disturbance can also occur and should be monitored.

Common Things People Notice

Diarrhea (most common side effect, about 1 in 6 people)
Trouble sleeping (insomnia)
Anxiety or low mood (depression)
General weakness or low energy

Common Side Effects

17%

Diarrhea— This is the most common side effect, affecting roughly 1 in 6 people.

Insomnia

Anxiety

Depression

Asthenia (weakness)

⚠️ Serious Side Effects

Suicidal ideation or tendencies (monitor mood closely).
Severe allergic reaction (Angioedema).
CNS depression or impairment (caution with driving and operating machinery until effects are known).

Drug Interactions

Acamprosate is renally excreted and not metabolized by the liver, so it has very few pharmacokinetic drug interactions compared with many other medications used in alcohol use disorder.

With: Alcohol

Risk: Continued alcohol use can blunt the medication’s benefit on abstinence.

Action: Avoid alcohol to get the full benefit of treatment.

With: No significant CYP interactions

Risk: Minimal, as acamprosate is not metabolized hepatically.

Action: No major cytochrome P450–related precautions are needed, but always review your full medication list with your prescriber.

Tapering & Discontinuation

Acamprosate is not associated with physiological dependence, so it can typically be stopped without tapering. Clinical follow-up is still important, as stopping may affect relapse risk.

Key Points

Acamprosate does not produce physical dependence or a withdrawal syndrome when stopped.
A formal taper is usually not required; however, abrupt discontinuation may still increase relapse risk if support is not in place.
Discuss any plan to stop acamprosate with your clinician so that your overall relapse-prevention plan can be adjusted.

Dosing & Administration

Adult Dosing

start: 666 mg three times daily

max: 1998 mg/day

notes: Lower doses (333 or 666 mg two times daily) may be considered in patients weighing less than 60 kg. Tablets should be swallowed whole; do not crush or chew.

Renal Dose Adjustments

Condition	Dose
Moderate (CrCl 30-50 mL/min)	333 mg TID
Severe (CrCl 30 mL/min or less)	Contraindicated

Hepatic Dose Adjustments

Mild to moderate (Child-Pugh A or B): No dosage adjustment necessary.

Patient-Friendly Explanation

The usual dose is 666 mg three times a day, often taken as two 333 mg tablets, three times daily. Take the tablets whole with fluid—do not crush or chew them. People with lower body weight may be prescribed a smaller dose.

Pregnancy, Breastfeeding, and Special Groups

Use acamprosate cautiously in special populations, with particular attention to renal function and the limited data available in pregnancy and lactation.

👶Pregnancy

Use only if the potential benefit justifies the possible risk to the fetus (often classified as Category C).

🤱Breastfeeding

It is not clear whether acamprosate passes into breast milk; use cautiously and consider the risks and benefits with the patient.

👧Children & Adolescents (Under 18)

Safety and efficacy have not been established in children and adolescents; not recommended.

👴Older Adults (65+)

Dosage should be adjusted according to renal function, which often declines with age.

Clinical Monitoring

Renal function at baseline and periodically, especially in older adults or those with known kidney disease.
Ongoing alcohol use and adherence to the medication regimen.
Mood symptoms and suicidality, particularly during early recovery.
Engagement in psychosocial treatment (counseling, mutual support groups, recovery programs).

Dosage Forms & Strengths

Enteric-coated tablets: 333 mg

How It Works

Acamprosate appears to stabilize the imbalance between excitatory (glutamate) and inhibitory (GABA) neurotransmission that occurs in chronic alcohol exposure, in part by decreasing activity at NMDA-type glutamate receptors. This reduces the hyperglutamatergic state associated with early abstinence.

Patient-Friendly Explanation

Long-term drinking leaves the brain in an overexcited state. Acamprosate helps quiet those overactive signals and support the brain’s calming systems, which can reduce physical cravings. It does not treat alcohol withdrawal symptoms.

Clinical Pearls & Place in Treatment

Acamprosate works best when started soon after detoxification and combined with structured psychosocial treatment, such as counseling or mutual support groups. It is not indicated for managing acute alcohol withdrawal, where benzodiazepines remain the mainstay. Because acamprosate is not metabolized by the liver and is renally excreted, it is often preferred in patients with significant liver disease but adequate kidney function.

Frequently Asked Questions

What is Acamprosate (Campral) used for?

Acamprosate is prescribed to help people with alcohol use disorder stay abstinent after they have stopped drinking. It supports long-term sobriety but is not a treatment for acute withdrawal symptoms.

Do I need to stop drinking before starting Acamprosate?

Yes. You should already be sober before starting acamprosate. It does not help you get through withdrawal safely and is not effective if you are still drinking regularly.

Can I drink alcohol while taking Acamprosate?

Drinking alcohol while on acamprosate may undermine the medication’s benefits and increase the risk of relapse. For best results, avoid alcohol completely and use this medication as part of a structured recovery plan that includes counseling and support.

How effective is Acamprosate at helping people stay sober?

In clinical trials, around 36% of people taking acamprosate remained completely abstinent for 6 months, compared with about 23.4% taking a placebo. While it is not a guarantee, it modestly improves the chances of maintaining sobriety when combined with psychosocial treatment.

Do I need to taper off Acamprosate when stopping it?

No taper is usually required because acamprosate does not cause physical dependence. However, you should still talk with your clinician before stopping, since changes in medication may affect your relapse risk and overall treatment plan.

This medication information is for educational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider before starting, stopping, or changing any medication. Never take medication without a prescription from a licensed healthcare provider.

Interested in this treatment?

This information is for educational purposes. Always consult with a qualified healthcare provider before starting any new treatment.

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Acamprosate (Campral)

FDA Approved 2004

Reviewed by the HeyPsych Medical Review Board

Board-certified psychiatrists and mental health professionals

Published November 24, 2025•Updated November 28, 2025•Reviewed November 24, 2025

Condition

Dose

Moderate (CrCl 30-50 mL/min)

333 mg TID

Severe (CrCl 30 mL/min or less)

Contraindicated