Acamprosate is a drug used for treating alcohol dependence. Acamprosate is thought to stabilize the chemical balance in the brain that would otherwise be disrupted by alcoholism, possibly by antagonizing glutamatergic N-methyl-D-aspartate receptors and agonizing gamma-aminobutyric acid (GABA) type A receptors. Reports indicate that acamprosate only works with a combination of attending support groups and abstinence from alcohol. Certain serious side effects include diarrhea, allergic reactions, irregular heartbeats, and low or high blood pressure, while less serious side effects include headaches, insomnia, and impotence. Acamprosate should not be taken by people with kidney problems or allergies to the drug. Ethanol acts in the central nervous system by binding to the GABAA receptor, increasing the effects of the inhibitory neurotransmitter GABA.