Glutamate modulator (anti-craving) 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 anti-craving agent used to maintain abstinence in alcohol dependence, taken as an adjunct to psychological support after detoxification.

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 excitatory glutamatergic and inhibitory GABAergic neurotransmission disrupted by chronic alcohol exposure, reducing the negative-reinforcement craving that drives relapse.

Prescribing in practice

It is started after assisted alcohol withdrawal is complete and should be continued even if a lapse occurs, as it supports ongoing abstinence rather than treating intoxication or withdrawal.
It is renally excreted and contraindicated in significant renal impairment, with dose adjustment needed in lesser impairment.
It works best as part of a structured programme combining medication with psychosocial support.

Monitoring

Monitor renal function before and during treatment along with drinking outcomes and continued engagement with support.

Counselling the patient

This medicine reduces the urge to drink and works best alongside counselling or support.
Keep taking it regularly, and continue even if you have a lapse, unless your team advises otherwise.
Diarrhoea is a common early side effect that often settles.

Evidence & guidelines

NICE recommends acamprosate as an option to support abstinence in alcohol dependence after successful withdrawal.

Reference: NICE CG115; SmPC Campral; 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