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Acamprosate

Generic name: acamprosate calcium
Brand name: Campral (discontinued)
Dosage form: oral delayed-release tablet
Drug class: Drugs used in alcohol dependence

Medically reviewed by Philip Thornton, DipPharm. Last updated on Apr 4, 2023.

What is acamprosate?

Acamprosate calcium is a prescription medication that helps people who are dependent on alcohol to abstain from drinking it. It is used along with psychosocial support and helps to prevent the cravings and urge to drink alcohol that people with alcohol use disorder experience.

Drinking alcohol alters the balance of the chemical messengers or neurotransmitters in your brain. Acamprosate is thought to work by helping to restore the balance of these neurotransmitters. It's thought that it primarily works by decreasing the excessive excitation that accompanies alcohol dependence.

Acamprosate is similar in structure - an analog of - two neurotransmitters called GABA (gamma-aminobutyric acid) and taurine. And while it's not clear exactly how it works, it's been suggested that acamprosate works by targeting GABA and NMDA (N-methyl-D-aspartate) glutamatergic receptor activity. It's also been suggested that it works by supplying calcium.

In 2004, the US Food and Drug Administration (FDA) approved a branded version of acamprosate calcium called Campral. Campral has since been discontinued, but generic versions of acamprosate calcium delayed-release tablets are available.

What is acamprosate used for?

Acamprosate is used for the maintenance of abstinence from alcohol in patients with alcohol dependence who are abstinent at treatment initiation. Acamprosate should be used as part of a comprehensive management program that includes psychosocial support.

Acamprosate is not used to help the symptoms of alcohol withdrawal.

Important information

Who should not take acamprosate?

Do not take acamprosate if you are allergic to acamprosate calcium or any of the other ingredients in it. Do not use acamprosate if you have severe renal impairment.

What should I tell my doctor before taking acamprosate?

Before taking acamprostate tell your healthcare provider about all of your medical conditions including if you:

How should I take acamprosate?

What happens if I miss a dose?

Missing doses of acamprosate may increase your chances of relapsing. If you miss a dose of acamprosate take your next dose as soon as you remember. If it is nearly time for your next dose, just take the next dose at the right time. Do not take double the dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222 if you take too much acamprosate. If you take too much acamprosate you may develop diarrhea. If you take too much acamprosate on a regular basis you may develop hypercalcemia or too much calcium in your blood.

What should I avoid while taking acamprosate?

Avoid drinking alcohol while taking acamprosate.

Dosing information

The recommended dose of acamprosate is 666 mg (two tablets) taken three times a day.

See full prescribing information for further details about acamprosate dosing.

What are the side effects of acamprosate?

Common side effects of acamprosate include:

These are not all of the possible side effects of acamprosate.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Interactions

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

Pregnancy and breastfeeding

Tell your doctor if you are pregnant or plan to become pregnant. Alcohol use during pregnancy can harm your unborn baby. The effects of acamprosate on the fetus are unknown, but it is thought that the drug crosses the placenta. Acamprosate should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known whether acamprosate crosses into breastmilk. Caution should be used when prescribing acamprosate for people who are breastfeeding because the effects of it on the baby are unknown.

Storage

Keep out of sight and reach of children.

What are the ingredients in acamprosate?

Active ingredients: acamprosate calcium

Inactive ingredients:

Zydus Pharmaceuticals acamprosate tablets: microcrystalline cellulose, magnesium stearate, methacrylic acid, polyethylene glycol 8000, povidone K90, silicon dioxide, sodium bicarbonate, sodium lauryl sulfate, sodium starch glycolate type A potato, talc

Mylan Pharmceuticals acamprosate tablets: ammonia, ferrosoferric oxide, silicon dioxide, glyceryl dibehenate, unspecified hypromellose, magnesium stearate, methacrylic acid - methyl methacrylate copolymer, microcrystalline cellulose, propylene glycol, shellac, talc

Glenmark Generics acamprosate tablets: silicon dioxide, unspecified crospovidone, methacrylic acid - ethyl acrylate copolymer (1:1) type A, magnesium stearate, microcrystalline cellulose, propylene glycol, sodium starch glycolate type A potato, talc, magnesium silicate, unspecified povidone

Acamprosate tablets made by other companies may contain different inactive ingredients. Check the product label for your specific version of acamprosate for a complete list of ingredients.

Generic acamprosate calcium delayed-release tablets are distributed by:

Popular FAQ

Acamprosate is pronounced a-KAM'-proe-sate.

Acamprosate and naltrexone are two different medications that are used in the treatment of alcohol use disorder. They work in different ways to help people who are dependent on alcohol to abstain from drinking it. Naltrexone is also used for the treatment of opioid use disorder.

Acamprosate was thought to be slightly more effective at helping people with alcohol use disorder remain off alcohol, while naltrexone was thought to be slightly more effective at helping reduce heavy drinking and cravings, according to the results of a meta-analysis which used data from 64 trials.

Results from two small studies, however, indicate that naltrexone is more effective than acamprosate in a number of areas. Continue reading

Acamprosate does not make you feel sick if you drink alcohol, unlike some other medications used in the treatment of alcohol use disorder (alcoholism). Continue reading

Acamprosate usually takes several days to a week to start working fully. About five days after you start taking this medication, you’ll reach a point where the amount of acamprosate in your system will remain at a consistent level if you continue to take it as prescribed. Continue reading

Weight gain is frequently reported as a side effect of acamprosate by people taking it to control alcohol cravings associated with alcohol use disorder. Continue reading

It’s not clear exactly how acamprosate works to help prevent the cravings and urge to drink alcohol that people with alcohol use disorder experience.

Acamprosate is thought to work by helping to restore the balance between excitatory and inhibitory neurotransmitters (chemical messengers) in the brain, which are altered by drinking alcohol. Research suggests it primarily works by decreasing the excessive excitation that accompanies alcohol dependence.

Continue reading

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.