People generally ignore them because of the positive effects the medications have on them. Weight gain is one among the most challenging antabuse adverse effects. Before using this medication, people should be warned of the possibility of gaining weight. Although most patients do not experience this side effect, for some it may be severe. The cause for this risk is not known, but it may be due to increased levels of insulin caused by the drug. The most common side effects of Antabuse are nausea, vomiting, diarrhea, constipation, dry mouth, headache, changes in appetite, depression or anxiety, irritability, insomnia, difficulty with concentration, tinnitus (ringing sound in the ears), urinary frequency, and vaginal discharge. These symptoms will go away when you stop taking the drug, but you should never take more than prescribed. If you experience any other problems while on this medication, call your doctor immediately. Antabuse is used to treat alcohol abuse. It works by blocking the effects of alcohol on the brain. This prevents users from experiencing its pleasurable effects and instead produces a nauseating feeling. Users are therefore less likely to drink alcohol and can quit the habit completely. However, it is important to note that despite its effectiveness in preventing drinking, it does not eliminate the desire for alcohol entirely. If you are still wanting to drink, then Antabuse won't help you.