OVERVIEW

Introduction

Acamprosate is a synthetic amino acid and a neurotransmitter analogue that is used as an alcohol deterrent in management of alcohol dependence and abuse. Acamprosate has not been linked to serum enzyme elevations during therapy and has not been linked to cases of clinically apparent liver injury.

Background

Acamprosate (a kam' proe sate) is N-acetylhomotaurine, a synthetic amino acid analogue similar to gamma aminobutyric acid (GABA) and taurine that has been shown to decrease alcohol craving in animal models. Acamprosate appears to function as a neurotransmitter which acts as a GABA agonist and partial glutamate (N-methyl-D-aspartate [NMDA]) antagonist, but its precise mechanism of action in decreasing alcohol craving is unknown. When used in a comprehensive alcohol treatment program, acamprosate has been shown to decrease relapse to alcohol use, at least over the short term. Acamprosate was approved for use in the therapy of alcohol dependence and abuse in the United States in 2004. Current indications are for maintenance of alcohol abstinence in patients with alcohol dependence who are abstinent at the time of drug initiation. Acamprosate is available in delayed release tablets of 333 mg generically and under the brand name Campral. The typical maintenance dose is 666 mg three times daily and it is recommended to be used only as a part of a comprehensive alcohol treatment program. The most common side effects are fatigue, anorexia, diarrhea, flatulence, nausea, headache, dizziness, insomnia, paresthesia, itching and sweating. Rare but potentially serious adverse events include suicidal ideation and behavior and hypersensitivity reactions.

Hepatotoxicity

Acamprosate therapy has not been associated with serum enzyme elevations over and above rates that occur with placebo therapy. Despite widescale use in alcohol treatment programs, there have yet to be published reports of clinically apparent acute liver injury attributed to acamprosate therapy.

Likelihood score: E (unlikely cause of clinically apparent liver injury).

Mechanism of Injury

Acamprosate is a synthetic amino acid, is minimally metabolized in the liver, and is excreted in the urine largely unchanged perhaps accounting for its lack of hepatotoxicity.

Drug Class: Substance Abuse Treatment Agents

PRODUCT INFORMATION

REPRESENTATIVE TRADE NAMES

Acamprosate – Generic, Campral®

DRUG CLASS

Substance Abuse Treatment Agents

COMPLETE LABELING

Product labeling at DailyMed, National Library of Medicine, NIH

CHEMICAL FORMULA AND STRUCTURE

ANNOTATED BIBLIOGRAPHY

References updated: 07 September 2021

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