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A very potent drug: ethyl alcohol.

Alcohol Affects The Brain

Considering the long experience of man with alcohol, is surprising how many drinkers are relatively ignorant of the way their favorite beverages affect them. The same applies to their non-drinking families and friends who may be concerned about why the drinker behaves as he does.

A grasp of the known facts about the effects of alcohol on the body-both short-term and long-term-is essential. Drinking is such a familiar part of our lifestyle that it is hard to realize that alcohol is a drug-every bit as active in the body as prescription drugs that are taken in carefully regulated dosages.

Alcohol's primary effects are in the central nervous system, the brain, although the whole body is affected. The familiar signs of drunkenness, such as slurred speech and unsteady gait, are not due to the direct action of alcohol on the tongue or legs, but by its effects on the parts of the brain which control their activities.

The speed with which alcohol brings drunkenness, and drunken behavior, depends upon the rate of its absorption. Unlike foods, alcohol does not have to be slowly digested. It is immediately absorbed into the blood, having passed directly through the walls of the stomach and small intestine. The blood rapidly carries it to the brain. Even the first few sips of an alcoholic beverage may cause changes in mood and behavior.

Alcohol is metabolized, burned and broken down, in the body at a fairly constant rate. As a person drinks faster than the alcohol can be burned, the drug accumulates in his body, resulting in higher and higher loads of alcohol in the blood. The larger the person, the greater the amount required to attain a given concentration of alcohol. In a 150-pound man, alcohol is burned at about the rate of one drink per hour.

No Way To Counteract Alcohol

The speed of alcohol absorption affects the rate at which one becomes drunk; in reverse, the speed of alcohol metabolism affects the rate at which one becomes sober again. Once in the bloodstream and carried throughout the body, alcohol undergoes the metabolic changes and eventually is reduced to carbon dioxide and water. Most of these processes take place in the liver, although from 2 to 5 percent of the alcohol is excreted chemically unchanged in urine, breath, and sweat.

As a general rule, it will take as many hours as the number of drinks consumed to sober up completely. Drinking black coffee, taking a cold shower, or breathing pure oxygen will not hasten the process.

Alcohol Affects Behavior

The first consistent changes in mood and behavior appear at blood alcohol levels of approximately 0.05 percent--that is 1 part alcohol to 2,000 parts blood. Thought, judgment, and restraint may be affected at this level, which would result from a 150-pound man taking two drinks in succession. He feels carefree, released from many of his ordinary tensions and inhibitions.

As more alcohol enters the blood, the depressant or "short-circuiting" action of alcohol involves more functions of the brain. At a level of 0.10 percent (1 part to 1,000) voluntary motor actions--hand and arm movements, walking, sometimes speech-become plainly clumsy.

At 0.20 percent (1 part to 500), the controls by the entire motor area of the brain are measurably impaired; that part of the brain which guides emotional behavior is also affected. The person staggers or he may want to lie down; he may be easily angered, or boisterous, or weep. He is "drunk."

At a concentration of 0.30 percent (1 part to 300), the deeper areas of the brain concerned with response to stimulus and understanding are dulled. At this level a person is confused or may lapse into stupor. Although aware, he has poor understanding of what he hears or sees.

With 0.40 or 0.50 percent alcohol in the blood (1 part to 250 or 200), he is out of the world; he is in coma. Still higher levels of alcohol in the blood block the centers of the lower brain which control breathing and heart beat, and death comes.

Blood-alcohol levels have important legal implications. In most States, an individual with a blood-alcohol level of 0.05 percent or less is legally presumed to be sober and in condition to drive a motor vehicle. A person with a level of 0.10 percent or 0.08 percent is legally presumed to be intoxicated or "under the influence" in some States.

Drinking by drivers plays a greater role as the severity of the crash increases. Up to 59 percent of fatal crashes and 25 percent of nonfatal crashes involved drinking drivers with blood alcohol concentrations (BAC) of 0.10 percent or higher.

The probability of crash involvement increases dramatically as a driver's BAC increases. The relative risk factor of being involved in or causing a crash at a BAC of 0.05 percent is one and a half times that at 0.02 percent. At a BAC of 0.10 percent, compared to 0.02, the risk doubles for being involved in a crash and quadruples for causing a crash.

30,000 Deaths -- 500,000 Maimed Yearly

Highway deaths have been rising steadily until nearly 60,000 Americans are now killed yearly. It has been shown that alcohol is involved in half of the highway fatalities. Drivers with chronic drinking problems are responsible for about two-thirds of the alcohol-related deaths. Young drivers and social drinkers with a high blood-alcohol level at the time of the accident cause the remaining one-third. These figures do not include 500,000 people injured annually, and many disabled, nor do they cover the immense costs in property damage, medical expenses, wage losses, insurance, etc.

Some studies show that alcohol tends to decrease fear and increase likelihood that an individual will accept risks. For example, when a group of bus drivers were given several drinks, they were more likely to try to drive their buses through spaces that were too narrow-and seemingly more willing to risk failure-than when they were sober. The judgment and skill impairment was not predictable on the basis of amount consumed: some drivers were more affected by two whiskeys than others were by six.

Reaction time is measured by the rapidity with which a subject makes a simple movement, such as pressing a button in response to a sound or visual signal. Below a blood alcohol level of 0.07 percent, reaction time varies little. Between 0.08 and 0.10 percent, reaction time slows measurably. Higher levels consistently produce larger performance failures. A much greater effect of alcohol on reaction time is found when attention is divided (a subject is engaged in another task at the same time).


Sharpness of visions seems relatively unaffected by alcohol. At high doses of alcohol, however, there is a decrease in ability to discriminate between lights of different intensities, and a narrowing of the visual field. The latter effect ("tunnel vision") may be particularly dangerous in automobile driving. Resistance to glare is impaired so that the eye requires longer to readjust after exposure to bright lights. Sensitivity to certain colors, especially red, appears to decrease.

Tests of muscular control or coordination show greater detrimental effects than on sensory capabilities. Intoxicating doses of alcohol impair most types of performance. A sensitive indicator of alcohol effect is the "standing steadiness" test. Alcohol increases swaying, especially if the eyes are closed. Coordination is also adversely affected by alcohol, as in tracing a moving object.

Other tests measuring both speed and accuracy suggest that alcohol has a greater effect on accuracy and consistency than on speed. A person who has had several drinks tends to "breeze through" a complex test but makes more errors than he normally would and is more erratic in his responses. Many subjects, however, feel their performance improved and refuse to believe the poor results.

Memory is strongly affected by a alcohol. Information learned by a person who has been drinking is not remembered as well as if the person was sober. This detrimental effect often goes unnoticed by the drinker.

Irreversible Brain Damage

Heavy drinking over many years may result in serious mental disorders or permanent, irreversible damage to the brain or peripheral nervous system. Mental functions such as learning ability, memory, and judgment can deteriorate severely, and an individual's personality structure and grasp on reality may disintegrate as well.

Even low doses of alcohol reduce sensitivity to taste and odors. Alcohol has little effect on the sense of touch, but dulls sensitivity to pain.

Several drinks before bedtime has been found to decrease the amount of REM (rapid eye movement) or dreaming sleep. The consequences are impaired memory and concentration, as well as anxiety, tiredness, and irritability.


Combined use of alcohol and other drugs frequently has supra-additive effects. These effects can be medically hazardous and occasionally are fatal. Impaired ability during performance of tasks such as driving is also dangerous, especially when the hazards are not recognized. Research results show that combined use can both increase physiologic danger and cause substantial behavioral change.

Nationally, alcohol in combination with other drugs is the second most frequent cause of drug-related medical crises. The minor tranquilizers are the drugs most frequently combined with alcohol and can increase the deleterious effects of alcohol on performance skills and alertness. In combination with alcohol, some of these tranquilizers can fatally depress cardiac functioning and respiration.

Alcohol Use Develops Tolerance

Drinking large amounts of alcohol over long periods of time seems to change the sensitivity of the brain to the effects of alcohol. This means that larger amounts of alcohol are required to produce the same effects. This adaptation is called "tolerance." It shows up in the chronic use of all addictive drugs.

The dependent person shows extraordinary adaptation to alcohol. He must take relatively huge amounts to produce the changes in feelings and behavior which he previously attained with smaller quantities. Moreover, his capacity to drink very large quantities without losing control of his actions also marks him as different from the moderate or heavy drinker. Later, in the chronic stage, tolerance decreases markedly until he may become drunk on relatively small amounts of alcohol.

At present, it is not known what accounts for the dramatic "behavioral tolerance" of the alcohol-dependent person to alcohol. Normal drinkers and alcoholic persons do not differ much in their overall rate of alcohol metabolism. This argues that the adaptive changes must occur in the brain rather than in the liver.


Another way in which the moderate or heavy drinker differs from the alcoholic person is that the abrupt removal of alcohol can produce severe mental and bodily distress in the alcoholic person. Whereas the normal drinker may experience the passing misery of the "hangover," the alcohol-dependent person may have severe trembling, hallucinations, confusion, convulsions, and delirium -- the alcohol withdrawal syndrome. The average person would have difficulty distinguishing between the common alcohol withdrawal syndrome involving anxiety, sweating, nausea, and the "shakes," and the more severe and potentially fatal condition known as delirium tremens. Both require immediate medical attention.

Alcohol (Ethanol) Use Highest

Since 1971, per capital alcohol consumption in the United States has been the highest since 1850, ranging from 2.63 to 2.69 gallons of absolute ethanol per person 14 years and older.

There are an estimated 9.3 to 10 million problems drinkers (including alcoholics) in the adult population of 145 million (18 years and over).

In addition to adult problem drinkers, there are an estimated 3.3 million problem drinkers among youth in the 14 to 17 age range-19 percent of the 17 million persons in this age group. (Youth problem drinking is defined differently than for adults because their problems tend to be acute--not chronic).

Increased availability of alcoholic beverages has occurred as a result of the lowering of the drinking age in several States, a trend to longer hours of sale, and an increase in the number of retail outlets.

Death Rates Higher For Drinkers

If one considers only the personal cost of drinking problems, the price is high. The life expectancy of alcoholic drinkers is shorter by 10 to 12 years than that of the general public. The mortality rate is at least two and one-half times greater, and they suffer more than their share of violent deaths. Alcoholism appears as a cause of death on more than 13,000 death certificates yearly. Undoubtedly, alcohol and its abuse contribute to many deaths which are attributed to other causes.

Studies have found that up to 40 percent of fatal industrial accidents, 69 percent of drownings, 83 percent of fire fatalities, and 70 percent of fatal falls were alcohol related. In a year, as many as 10,000 suicides were related to alcohol use, and up to 8,400 alcoholics committed suicide. It is estimated alcohol-related deaths may run as high as 205,000 per year. Clinical studies consistently show that various types of alcohol problems in males are associated with mortality rates two to six times higher than rates in the general population.

Alcohol Contributes To Violence

More than half of the Nation's alcoholics are employed. Employees with drinking problems are absent from work about 2 1/2 times as frequently as the general work force.

For some drinkers, alcohol releases violent behavior that might be unlikely or even unthinkable in their sober state. Half of all homicides and one-third of all suicides are alcohol-related-accounting for about 11,700 deaths yearly. Alcohol is also frequently involved in assaults and offenses against children. A California study of over 2,000 felons concluded that "problem drinkers were more likely to get in trouble with the law because of their behavior while drinking or because they needed money to continue drinking."

Alcohol figures in less violent criminal behavior as well. For example, almost half of the 5 1/2 million arrests yearly in the United States are related to the misuse of alcohol. Drunkenness accounts for approximately 1,400,000 arrests, while disorderly conduct and vagrancy-used by many communities instead of the public drunkenness charge-account for 665,000 more. Intoxicated drivers make up the 335,000 remaining arrests. Cost to taxpayers for the arrest, trial, and keeping in jail of these persons has been estimated at more than $100 million a year.

Alcohol abuse and alcoholism cost the United States nearly $43 billion each year--including $19.64 billion in lost production, $12.74 billion in health and medical costs, $5.14 billion in motor vehicle accidents, $2.86 billion in violent crimes, $1.94 billion in social responses, and $0.43 billion in fire losses.

Effects of alcoholism are not limited to the drinker alone. His victims, his employers, and society are all harmed by his behavior. Impoverished families, broken homes, desertion, divorce, and deprived or displaced children are also parts of the toll. Costs to support families disabled by alcohol problems amount to additional millions of tax dollars each year.

Some Health Consequences of Alcohol Use

When taken in large doses over long period of time, alcohol can prove disastrous, reducing both the quality and length of life. Heavy drinkers have long been known to have lowered resistance to pneumonia and other infectious diseases. 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.


Alcohol and its metabolic product, acetaldehyde, have specific effects on the heart muscle that can result in disease. Alcoholic cardiomyopathy is believed to be caused by the toxic effects of alcohol or its metabolic products on the myocardium. Its symptoms are chronic shortness of breath and signs of congestive heart failure. It causes heart enlargement, abnormal heart signs, edema, enlargement of the spleen or liver, noisy breathing, electrocardiographic abnormalities, and disturbances of cardiac rhythm and conduction. Some reports indicate that heavy chronic drinking predisposes an individual to coronary artery disease. Additionally, there is evidence that alcohol can produce angina pectoris.

Irregularities in the heartbeat occur both in patients with alcohol-related diseases and in other individuals during alcohol intoxication. Ventricular fibrillation and palpitations caused by alcohol intoxication are common. In a study of 15 severely intoxicated men, 3 went into cardiac arrest, 11 showed disturbed heart rhythm, and 2 evidenced low blood pressure; these effects have been duplicated in numerous studies.

It is likely that alcohol-induced cardiac arrhythmia is due to both the direct effect of alcohol on the heart muscle and the effects of either alcohol or acetaldehyde on the heart's conduction system. Alcohol intoxication has been shown to affect the atrioventricular node so as to cause a complete heart block requiring pacemaker therapy. Alcohol can have a very harmful effect on patients already suffering from heart disease. It has been shown, for example, that patients with cardiac disease experience a fall in cardiac and stroke index, indicating increased vulnerability, after drinking even one cocktail.


Some physiologic studies have indicated changes in cardiac hemodynamics (including blood pressure) which appear to depend on the type of measurement and the presence or absence of cardiac disease. An epidemiologic study of nearly 84,000 individuals, however, has demonstrated a highly significant increase in diastolic and systolic blood pressure in those who consumed three or more drinks per day.


Liver damage especially may result from heavy drinking. Cirrhosis of the liver occurs about eight times as often among alcoholic individuals as among non-alcoholics. Although it is the primary site for detoxification of alcohol, the liver can be damaged by alcohol and its metabolic products. Alcohol has a number of metabolic effects on the liver. For one, it inhibits the conversion of amino acids to glucose, a major energy-producing fuel in the body, when the liver's store of glucose is low (as is often the case in poorly nourished alcoholics). The resulting hypoglycemia is similar to the condition of reduced blood sugar seen in diabetics who have taken too much insulin.

Still another consequence is the inhibition of the conversion of amino acid into certain important proteins manufactured by the liver. Included are albumin, tranferrin, complement, and several others involved in blood coagulation.

At the same time, alcohol can also stimulate hepatic synthesis of certain other proteins, including lipoproteins, which transport fats in the blood. This effect may explain the elevated blood triglyceride (fat) levels frequently seen after alcohol ingestion. The alteration in fat metabolism may result in a gradual accumulation of fat in the liver and cause a "fatty liver." This condition can cause liver failure and death, particularly in younger people.

Alcoholic hepatitis is a major life-threatening complication of heavy chronic alcohol consumption, and may be a precursor stage of cirrhosis. The production and progression of the diseases influenced by tissue lymphocytes, which invade the liver in an apparent immunologic allergic reaction of individuals to their own hyaline. This reaction appears to continue even when patients give up alcohol because the preexisting hyaline bodies remain in the liver. Cirrhosis is a chronic inflammatory disease of the liver in which functioning liver cells are replaced by scar tissue.


Indisputably, alcohol is one cause of cancer. Drinking alcoholic beverages exposes the drinker to an increase in the risk of cancer at various body sites. Heavy drinking increases the risk of developing cancer of the tongue, mouth, oropharynx, hypopharynx, esophagus, larynx, and liver. In the U.S., these sites represent 6.1 to 9.1 percent of all cancers in the white population and 11.3 to 12.5 percent among the black.

Alcohol has a synergistic effect with tobacco that increases the risk of cancer. For example, one study showed that the risk of head and neck cancers for heavy drinkers who smoked was 6 to 15 times greater than for those who abstain from both. Another study showed a risk of esophageal cancer 44 times greater for heavier users of both alcohol and tobacco, as compared to 18 times greater for heavier users of alcohol only and 5 times greater for heavier users of tobacco only.


It is clear that alcohol can damage the esophagus by direct chemical irritation to its mucus (interior lining), by inducing severe vomiting that tears the mucus, or by interfering with normal motor functions, thereby causing an upward movement of stomach acid into the esophagus where it can erode the tissue. The major complication in these processes is hemorrhage, accompanied

or preceded by local pain and difficulty in swallowing.


Gastric damage as a result of alcohol ingestion was first observed by Beaumont in 1833 in a patient whose recovery from a gunshot wound left a permanent opening in his abdominal wall. The opening led to the interior of the stomach, through which Beaumont could study the effects on the stomach lining of various ingested substances. Alcohol caused acute gastric damage accompanied by bleeding.

Alcohol subsequently has been show to be widely associated with a variety of inflammatory and bleeding lesions of the stomach. The degree of the damage appears to be related to alcohol concentration, with damage to the cells occurring rapidly after alcohol ingestion.


Digestive disturbances in the small intestine are common in alcoholics. Acute administration of alcohol leads to changes in intestinal motility. In the jejunum (the division of the small intestine below the duodenum), impeding peristaltic waves are decreased by alcohol and propulsive waves are unchanged, resulting in an increased rate of propulsion through the small intestine.


Alcoholism is associated with a significant increase in the incidence of pancreatitis, a chronic inflammation of the pancreas. Most researchers believe that the disease-causing mechanism is the alcohol-induced increase in protein concentration in pancreatic juice, thought to precipitate and form obstructive plugs in the ducts of the organ.


Tests have revealed consistently that large doses of alcohol frustrate sexual performance. Studies of alcoholic persons have revealed that their sex life was disturbed, deficient, and ineffectual. Impotence may result, sometimes reversible with the return of sobriety.


Research on the impact of maternal alcohol consumption on human infants has demonstrated the fetal alcohol syndrome (FAS) is a clinically observable abnormality. A high blood alcohol level during a critical time of embryonic development probably is necessary to produce FAS. The average alcohol consumption may not be as important as maximum concentrations during critical periods.

Undoubtedly, there are many more cases in which only part of the syndrome is found. These may be instances of single malformations, retarded growth and development, or behavioral patterns. Brain lesions may occur in individuals who do not show other features of the FAS. Common neuropathologic findings are widespread malformations resulting from failure of the brain cells to migrate to their proper location.

The projected incidence of the fetal alcohol syndrome makes it the third cause of birth defects with associated mental retardation--following only Down's Syndrome and spina bifida--and the only one of the three preventable.
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Publication:Pamphlet by: Narcotic Educational Foundation of America
Article Type:pamphlet
Date:Jun 20, 1991
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