|
This information has been developed and provided by an independent third-party source. Merck & Co., Inc. does not endorse and is not responsible for the accuracy of the content, or for practices or
standards of non-Merck sources.
Pronunciation
(a kam PROE sate)
Generic Available
No
Index Terms
U.S. Brand Names
Canadian Brand Names
Pharmacologic Category
Use: Labeled Indications
Maintenance of alcohol abstinence
Pregnancy Risk Factor
C
Pregnancy Considerations
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
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).
Dosage form specific issues:
• Sulfites: Traces of sulfites may be present in the formulation.
Adverse Reactions
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 & 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
Drug Interactions
There are no known significant interactions.
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).
Storage
Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).
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)
Dosage
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.
Administration: Oral
May be administered without regard to meals. Tablet should be swallowed whole; do not crush or chew.
Dietary Considerations
Abstinence is required during treatment. May be taken without regard to meals. Each 333 mg tablet contains 33 mg of elemental calcium.
Patient Education
Taking this medication helps maintain abstinence only when used as part of a treatment program that includes counseling and support. Swallow tablet whole. Do not chew or crush. Can cause drowsiness. You may experience diarrhea, peripheral edema, insomnia, anxiety, depression, and generalized weakness. Report persistent diarrhea, excessive or sudden weight gain, swelling of extremities, respiratory difficulties, fainting, or thoughts of suicide.
Geriatric Considerations
Initial studies did not include sufficient geriatric patients to be able to derive sufficient data to compare elderly to younger adults. Only 41 out of 4234 patients in clinical trials were ≥65 years of age with none ≥75 years. However, since this medication is cleared renally exclusively, caution should be used since many elderly have Clcr 30-50 mL/minute where dosage reduction is required (see Dosage).
Dental Health: Effects on Dental Treatment
Key adverse event(s) related to dental treatment: Xerostomia and changes in salivation (normal salivary flow resumes upon discontinuation) and taste perversion.
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Nursing: Physical Assessment/Monitoring
May cause depression. Monitor for suicide ideation.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, delayed release, enteric coated, oral, as calcium:
Campral®: 333 mg [contains calcium 33 mg/tablet, sulfites]
Pricing: U.S. (www.drugstore.com)
Tablet, EC (Campral)
333 mg (180): $161.24
References
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.
International Brand Names
Lexi-Comp.com
Last full review/revision March 2011
|
