Note: Many adverse effects associated with treatment may be related to alcohol abstinence; reported frequency range may overlap with placebo.
>10%: Gastrointestinal: Diarrhea (10% to 17%)
1% to 10%:
Cardiovascular: Syncope, palpitation, edema (peripheral)
Central nervous system: Insomnia (6% to 9%), anxiety (5% to 8%), depression (4% to 8%), dizziness (3% to 4%), pain (2% to 4%), paresthesia (2% to 3%), headache, somnolence, amnesia, tremor, chills
Dermatologic: Pruritus (3% to 4%), rash
Endocrine and metabolic: Weight gain, libido decreased
Gastrointestinal: Anorexia (2% to 5%), flatulence (1% to 3%), nausea (3% to 4%), abdominal pain, dry mouth (1% to 3%), vomiting, dyspepsia, constipation, appetite increased, taste perversion
Genitourinary: Impotence
Neuromuscular & skeletal: Weakness (5% to 7%), back pain, myalgia, arthralgia
Ocular: Abnormal vision
Respiratory: Rhinitis, dyspnea, pharyngitis, bronchitis
Miscellaneous: Diaphoresis (2% to 3%), suicide attempt
<1%, postmarketing, and/or case reports (limited to important or life-threatening): Angina, asthma, exfoliative dermatitis, gastrointestinal hemorrhage, hallucinations, hypothyroidism, MI, ophthalmitis, pancreatitis, photosensitivity, psychosis, pulmonary embolus, renal calculus, renal failure, seizure, suicidal ideation, suicide attempts, suicide completion
Ethanol: Abstinence is required during treatment. Ethanol does not affect the pharmacokinetics of acamprosate; however, the continued use of ethanol will decrease desired efficacy of acamprosate.
Food: Food decreases absorption of acamprosate (not clinically significant).
Distribution: Vd: 1 L/kg
Protein binding: Negligible
Metabolism: Not metabolized
Bioavailability: 11%
Half-life elimination: 20-33 hours
Excretion: Urine (as unchanged drug)
Oral: Adults: Alcohol abstinence: 666 mg 3 times/day (a lower dose may be effective in some patients) Adjustment in patients with low body weight (unlabeled): A lower dose (4 tablets/day) may be considered in patients with low body weight (eg, <60 kg).
Note: Treatment should be initiated as soon as possible (following the period of alcohol withdrawal) when the patient has achieved abstinence.
Dosage adjustment in renal impairment:
Clcr 30-50 mL/minute: Initial dose should be reduced to 333 mg 3 times/day.
Clcr<30 mL/minute: Contraindicated in severe renal impairment.
Brasser SM, McCaul ME, and Houtsmuller EJ, "Alcohol Effects During Acamprosate Treatment: A Dose-Response Study in Humans,"Alcohol Clin Exp Res, 2004, 28(7):1074-83.
Graham R, Wodak AD, and Whelan G, "New Pharmacotherapies for Alcohol Dependence,"Med J Aust, 2002, 177(2):103-7.
Overman GP, Teter CJ, and Guthrie SK, "Acamprosate For the Adjunctive Treatment of Alcohol Dependence,"Ann Pharmacother, 2003, 37(7-8):1090-9.
