Anti-craving Agent — Alcohol Relapse Prevention (GABA/Glutamate Modulator) Pregnancy: No adequate human data; use in pregnancy only after careful benefit/risk assessment (when the patient cannot abstain from alcohol without treatment).

Acamprosate Calcium

Brand names: Campral EC

Acamprosate calcium is an oral medicine used to help maintain abstinence in alcohol-dependent patients after detoxification, as part of a programme that includes psychosocial support.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 666 mg (two 333 mg tablets)

Route: Oral

Frequency: Three times daily

Maintenance of abstinence in alcohol dependence. Adults 18-65 years weighing 60 kg or more: 2 tablets three times daily with meals (morning, noon and night). Subjects under 60 kg: 4 tablets/day divided (2 morning, 1 noon, 1 night). Recommended treatment period is one year; initiate after the withdrawal period once the patient is abstinent. Swallow tablets whole - do not chew or crush (gastro-resistant coating). Not for use in children, adolescents or the elderly.

Dose adjustments

Renal

Contraindicated in patients with renal impairment (serum creatinine >120 micromol/l) per UK SPC.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or any excipient
Breast-feeding women
Renal impairment (serum creatinine >120 micromol/l)

Side effects

Diarrhoea (very common)
Abdominal pain, nausea, vomiting, flatulence
Pruritus, maculo-papular rash
Decreased libido; frigidity or impotence
Very rare: hypersensitivity reactions including urticaria, angio-oedema or anaphylactic reactions

Interactions

Acidic drugs eliminated by active renal secretion, e.g. NSAIDs - clinically relevant interactions may occur
Diltiazem: combination may lead to worsening of angina pectoris
Naltrexone: co-administration increased acamprosate Cmax by 33% and AUC by 25% (no dose adjustment recommended)

Clinical monograph

How it works

It is thought to restore the balance between glutamatergic and GABAergic neurotransmission that is disturbed by chronic alcohol exposure, helping to reduce the negative reinforcement and craving associated with abstinence.

Prescribing in practice

Acamprosate is renally excreted and is contraindicated in significant renal impairment, so assess renal function before and during treatment.
It is most effective started promptly after detoxification and continued for an extended period alongside psychosocial support, and may be continued even if a lapse occurs.
It does not cause an aversive reaction with alcohol and does not treat withdrawal; prescribe within an alcohol-treatment programme per current prescribing references.

Monitoring

Monitor renal function and review adherence, alcohol use and engagement with psychosocial support during treatment.

Counselling the patient

Explain that this medicine helps reduce the urge to drink and supports staying abstinent, but does not stop withdrawal.
Encourage continuing the medicine and support even after a slip, unless advised otherwise.
Advise that combining it with counselling or support services improves the chance of success.

Evidence & guidelines

NICE recommends acamprosate as an option to support abstinence in alcohol dependence alongside psychological intervention, supported by trial evidence for maintaining abstinence.

Reference: NICE CG115 (Alcohol Dependence); NICE NG115; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways