Acamprosate

U.S. BRAND NAMES — Campral®
PHARMACOLOGIC CATEGORY GABA Agonist/Glutamate Antagonist
DOSING: ADULTS — Alcohol abstinence: Oral: 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.
DOSING: ELDERLY — Refer to adult dosing.
DOSING: 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.
DOSAGE FORMS — Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, enteric coated, delayed release, as calcium: 333 mg [contains calcium 33 mg and sulfites]
DOSAGE FORMS: CONCISE Tablet, enteric coated, delayed release: Campral®: 333 mg
GENERIC EQUIVALENT AVAILABLE — No
ADMINISTRATION — May be administered without regard to meals. Tablet should be swallowed whole; do not crush or chew.
USE — Maintenance of alcohol abstinence
ADVERSE REACTIONS SIGNIFICANT 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
CONTRAINDICATIONS — Hypersensitivity to acamprosate or any component of the formulation; severe renal impairment (Clcr <30 mL/minute)
WARNINGS / PRECAUTIONS Concerns related to adverse effects: Suicidal ideation/attempt: Attempted and completed suicides have occurred in acamprosate-treated patients; use with caution in suicidal ideation. Monitor for depression and/or suicidal thinking.
Disease-related concerns: Alcohol dependence: Appropriate use: Should be used as part of a comprehensive program to treat alcohol dependence. Treatment should be initiated as soon as possible following the period of alcohol withdrawal, when the patient has achieved abstinence. Acamprosate does not eliminate or diminish the symptoms of alcohol withdrawal. Renal impairment: Use with caution in patients with moderate renal impairment (Clcr 30-50 mL/minute).
Special populations: Pediatrics: Safety and efficacy have not been established in children.
Dosage form specific issues: Sulfites: Traces of sulfites may be present in the formulation.
DRUG INTERACTIONS — No clinically-significant drug-to-drug interactions have been identified.
ETHANOL / NUTRITION / HERB INTERACTIONS 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).
PREGNANCY RISK FACTOR — C (show table)
PREGNANCY IMPLICATIONS — Teratogenic in animal studies. No adequate or well-controlled studies in pregnant women; use only if potential benefit outweighs possible risk to the fetus.
LACTATION — Excretion in breast milk unknown/use caution
DIETARY CONSIDERATIONS — May be taken without regard to meals. Each 333 mg tablet contains 33 mg of elemental calcium.
PRICING — (data from drugstore.com)Tablet, EC (Campral) 333 mg (180): $121.36
TOXICOLOGY / OVERDOSE COMPREHENSIVE — Symptoms may include diarrhea and (in chronic overdose) hypercalcemia. Treatment is symptom-directed and supportive.
INTERNATIONAL BRAND NAMES — Acampral (KR); Aotal (FR); Campral (AR, AT, AU, BE, BR, CH, CL, DE, DK, ES, GB, HU, IE, NL, PL, RU, SE); Sobrial (ZA)
MECHANISM OF ACTION — Mechanism not fully defined. Structurally similar to gamma-amino butyric acid (GABA), acamprosate appears to increase the activity of the GABA-ergic system, and decreases activity of glutamate within the CNS, including a decrease in activity at N-methyl D-aspartate (NMDA) receptors; may also affect CNS calcium channels. Restores balance to GABA and glutamate activities which appear to be disrupted in alcohol dependence. During therapeutic use, reduces alcohol intake, but does not cause a disulfiram-like reaction following alcohol ingestion.
PHARMACODYNAMICS / KINETICS Distribution: Vd: 1 L/kg
Protein binding: Negligible
Metabolism: Not metabolized
Bioavailability: 11%
Half-life elimination: 20-33 hours
Excretion: Urine (as unchanged drug)