Although alcohol is often thought of as a stimulant, it's actually a depressant, containing ethanol (ETH-eh-nall), which is a mood-altering drug. Even a small amount of alcohol will generally relax your body, causing you to become less inhibited, and in some cases, more friendly and outgoing. Alcohol also affects your motor ability, including reaction time, muscle coordination, eyesight, and depth perception. Large quantities of alcohol can induce sleep, and can even result in a life-threatening coma by severely depressing the vital centers of your nervous system. However, your body will usually reject the alcohol by causing you to vomit before you're in serious jeopardy. When alcohol is consumed, side effects begin almost immediately. This is because 95 percent of alcohol isn't digested, but absorbed directly through the stomach lining into your bloodstream, then carried to your brain. Although some alcohol is removed from your system through urination, perspiration, and by breathing, most of the substance is eventually carried to your liver, where it's broken down into carbon dioxide and water. However, your liver can only process one-third of an ounce of alcohol per hour. This is a fixed rate, so only time, not black coffee or a cold shower is effective in sobering you up when you're drunk. Since alcohol depletes your body of water, you'll often experience headaches, upset stomach, and dehydration the next day. For more information about the effects of alcohol, contact a health care professional in your area.