Since alcohol-dependent persons have an increased tolerance for alcohol, they react differently than moderate or heavy drinkers to the effects of alcohol. They can drink large quantities of alcohol without losing control of their actions, while the moderate or heavy drinker cannot. Instead of becoming more pleasant and relaxed as do the moderate or heavy drinkers, alcoholics may become progressively more tense and anxious while drinking. They may accurately perform complex tasks at blood-alcohol levels several times as great as those that would incapacitate moderate to heavy drinkers. At one stage of their alcoholism, they may drink a fifth of whiskey a day without showing signs of drunkenness. Later, in the chronic stage, their tolerance decreases to the point that they may become drunk on relatively small amounts of alcohol. Alcoholics also differ from moderate to heavy drinkers in their reactions to the abrupt removal of alcohol. The normal drinker may only experience the prosing misery of the hangover. Alcoholics may suffer severe mental and bodily distress, such as severe trembling, hallucinations, confusion, convulsions, delirium (the alcohol withdrawal syndrome), and delirium tremens. Both the alcohol withdrawal syndrome and delirium tremens involve shaking, sweating, nausea, and anxiety. However, delirium tremens can cause death. The average person would have difficulty distinguishing between the alcohol withdrawal syndrome and the delirium tremens. Both require immediate medical attention. At present, no one knows the reason for the increased tolerance of the alcohol-dependent person to alcohol. At one time tolerance levels were thought to depend on differences in people’s rates of alcohol metabolism. However, overall rates of alcohol metabolism were later found not to differ much in normal drinkers and alcoholics. That fact indicated changes in tolerance levels must occur in the brain rather than in the liver. DRUG INTERACTIONS WITH ALCOHOL. – Alcohol works on the same brain areas as some other drugs. Drinking alcohol within a short time before or after t aking those drugs can multipl y the normal effects of either the drug or the alcohol taken alone. For example, alcohol and barbiturates taken in combination increase the effects of each other on the central nervous system, which can be particularly dangerous. Alcohol taken in combination with any drug that has a depressant effect on the central nervous system is likewise dangerous. These dangerous reactions are the result of metabolism–the way our bodies chemically process what we consume. If drugs were not metabolized within the body, their effect would continue for the remainder of a person’s life. In the metabolic process, our bodies transform drugs into other substances and eventually eliminate them through normal bodily functions. The more rapid the rate of metabolism, the lower the impact of the drug. When drugs are forced to compete with alcohol for processing by the body, alcohol is metabolized first; the other drug then remains active in the blood for an extended time. As a result, the effect of the drug on the body is exaggerated since its metabolism is slowed down by the body’s tendency to take care of the alcohol first. When added to the normal depressant consequence of alcohol, further depression of the nervous system, which regulates vital body functions, occurs. That serious condition can result in death. Although anyone’s body metabolizes drugs more slowly when the blood contains alcohol, the alcoholic’s [or heavy drinker’s] body metabolizes drugs more rapidly during sober periods. Therefore, heavy drinkers commonly take even larger doses of drugs. The usual quantities taken by nondrinkers or moderate drinkers would have little effect on the heavy drinker. The results of taking large doses of drugs and then drinking can place these persons in even greater jeopardy; the results can be fatal. LONG-TERM EFFECTS. –Drinking alcohol in moderation apparently does the body little permanent harm. But when taken in large doses over long periods, alcohol can prove disastrous; it can reduce both the quality and length of life. Damage to the heart, brain, liver, and other major organs may result. Prolonged heavy drinking has long been known to be connected with various types of muscle diseases and tremors. One essential muscle affected by alcohol is the heart. Some recent research suggests that alcohol may be toxic to the heart and to the lungs as well. Liver damage especially may result from heavy drinking. Cirrhosis of the liver occurs about eight times more often among alcoholics as among nonalcoholics. Heavy drinkers have long been known to have lowered resistance to pneumonia and other infectious diseases, usually because of malnutrition. However, recent research showing well-nourished heavy drinkers may also have lowered resistance indicates that alcohol directly interferes with the immunity system. People with blood-alcohol levels of 0.15 to 0.25 percent have a 3-17