Acamprosate

Sujin Lee Weinstein, PharmD, BCPP

INDICATIONS

FDA

FORMS

Brand name

Generic

Dose strength

Campral

Acamprosate

333 mg tablets (enteric coated, delayed release)

ADULT DOSING

USUAL

  • Traditional dosing: 666 mg three times a day
  • Alternative dosing: 999 mg twice-daily; may improve adherence (long half-life permits twice-daily dosing)

RENAL

  • Cr Cl 30 – 50 mL/min: 333 mg three times a day
  • Cr Cl is < 30 mL/min: use is contraindicated

ADMINISTRATION

  • Initiate after alcohol withdrawal and the patient achieves a period of alcohol abstinence to improve tolerability
  • May be taken with or without food; however, taking with meals, three times a day, may enhance treatment adherence and reduce GI side effects
  • Should be continued, even if relapse occurs

MECHANISM OF ACTION

  • Restores the imbalance of excitatory GABA and inhibitory glutamate neurotransmitters

PHARMACOKINETICS

ABSORPTION

  • Food reduces bioavailability; however, food may enhance treatment adherence and reduce GI side effects

METABOLISM

  • Does not undergo metabolism; the major route of excretion is by the kidneys

HALF-LIFE

  • 20 – 33 hours (longer with renal impairment)

DRUG INTERACTIONS

  • Lacks CYP drug interactions because it does not affect the CYP systems

WARNINGS AND PRECAUTIONS

COMMON SIDE EFFECTS

  • Asthenia, anorexia, diarrhea, dizziness, flatulence, headache, insomnia, nausea, paresthesia, pruritis, sweating, vomiting
  • Gastrointestinal side effects are dose related and often decline with continued use.

PRECAUTIONS

  • Depression and suicidality – may occur with alcohol use, alcohol dependence and alcohol withdrawal

SPECIAL POPULATIONS

PEDIATRICS

  • Safety and effectiveness have not been established.

GERIATRICS

  • Age-related changes in metabolism and excretion may increase levels and effects.

PREGNANCY

  • Use with caution
  • Animal studies suggest teratogenicity.
  • Limited data in humans suggest low risk of teratogenicity.
  • Weigh benefits and risks of acamprosate treatment during pregnancy, including the risk of fetal alcohol syndrome associated with continued alcohol use

LACTATION

  • Use with caution
  • Inadequate information
  • Very poor maternal oral bioavailability (11%) – anticipate minimal systemic effects in infant

MONITORING RECOMMENDATIONS

Parameter

Frequency

Rationale

Renal function

  • Treatment initiation
  • Annually
  • As clinically indicated
  • Adjust dose based on renal function

Changes in behavior or mood

  • Treatment initiation
  • Annually
  • As clinically indicated
  • Depression and suicidality

EXPERT COMMENTS

  • Since acamprosate is not metabolized by the liver, it is an appealing alternative for patients with hepatic impairment, e.g. patients with advanced alcohol use disorder.
  • Lacks the disulfiram-ethanol reaction when taken with alcohol and does not precipitate opioid withdrawal that may occur with disulfiram and naltrexone, respectively
  • Thrice-daily dosing is often an issue – dosing with meals or twice daily may improve adherence.
  • Not an ideal agent for patients with significant renal impairment (contraindicated for use in patients with Cr Cl < 30mL/min)

References

  1. Acamprosate. In: Drugs and Lactation Database (LactMed®). Bethesda (MD): National Institute of Child Health and Human Development; September 19, 2022.
  2. Coe C, Patel A, Lawrence D. Pharmacotherapy options for alcohol use disorder in patients with alcohol-associated liver disease: a brief guide for clinicians. Clin Liver Dis (Hoboken). 2023;21(5):125-129.  [PMID:37936927]
  3. Kelty E, Tran D, Lavin T, et al. Prevalence and safety of acamprosate use in pregnant alcohol-dependent women in New South Wales, Australia. Addiction. 2019;114(2):206-215.  [PMID:30152012]
  4. Kelty E, Terplan M, Greenland M, et al. Pharmacotherapies for the Treatment of Alcohol Use Disorders During Pregnancy: Time to Reconsider? Drugs. 2021;81(7):739-748.  [PMID:33830479]
  5. Quintrell E, Russell DJ, Rahmannia S, et al. The Safety of Alcohol Pharmacotherapies in Pregnancy: A Scoping Review of Human and Animal Research. CNS Drugs. 2025;39(1):23-37.  [PMID:39388037]
Last updated: September 14, 2025