Explain the acute physiological effects alcohol has on the body. Make sure to include toxic reactions, the St. Bernard Myth, diuretic effects, effects on sleep, effects on pregnancy, and interactions with other drugs

Question

What will be an ideal response?

Answer 1

Answer: Toxic Reactions Death by asphyxiation can happen if BAC levels are elevated, generally when they reach 0.50 percent. In general, the therapeutic index for alcohol, as measured by the LD50/ED50 ratio, is approximately 6. This figure is not very high, and caution is strongly advised; the risks of being the "big winner" in a drinking contest should be weighed very carefully. On the one hand, to achieve a lethal BAC level of 0.50 percent, a 165-pound man needs to have consumed approximately twenty-three drinks over a four-hour period. On the
other hand, consuming ten drinks in one hour, a drinking schedule that achieves a BAC level of 0.35 percent, puts a person in extremely dangerous territory. We need to remember that LD50 is the average level for a lethal effect; there is no way to predict where a particular person might be located on the normal curve! Fortunately, two mechanisms are designed to protect us to a certain degree. First, alcohol acts as a gastric irritant so the drinker often feels nauseated and vomits. Second, the drinker may simply pass out, and the risk potential from further drinking becomes irrelevant. Nonetheless, there are residual dangers in becoming unconscious; vomiting
while in this state can prevent breathing, and death can occur from asphyxiation.

Heat Loss and the Saint Bernard Myth
Alcohol is a peripheral dilator, which means that blood vessels near the skin surface enlarge, leading to a greater amount of blood shunted to the skin. The effect gives you the feeling that your skin is warm, which is most likely the basis for the myth that alcohol can keep you warm in freezing weather. In truth, however, peripheral dilation causes core body temperature to decrease. In other words, alcohol produces a greater loss in body heat than would occur without it. So, if you are marooned in the snow and you see an approaching Saint Bernard with a cask of brandy strapped to its neck, politely refuse the offer. It will not help and could very well do you harm.

Diuretic Effects
As concentration levels rise in the blood, alcohol begins to inhibit antidiuretic hormone (ADH), a hormone that normally acts to reabsorb water in the kidneys prior to elimination in the urine. As a result, urine is more diluted and, because large amounts of liquid are typically being consumed at the time, more copious. Once blood alcohol concentrations have peaked, however, the reverse
occurs. Water is now retained in a condition called antidiuresis, resulting in swollen fingers, hands, and feet.

This effect is more pronounced if salty foods (peanuts or pretzels, for example) were eaten along with the alcohol. The inhibition of ADH during the drinking of alcoholic beverages can be a serious concern, particularly following vigorous exercise when the body is already suffering from a loss of water and fluid levels are low.

Effects on Sleep It might seem tempting to induce sleep with a relaxing "nightcap," but in fact the resulting sleep patterns are adversely affected. Alcohol reduces the duration of a phase
of sleep called rapid eye movement (REM) sleep. Depending on the dose, REM sleep can be either partially or completely suppressed during the night. When alcohol is withdrawn, REM sleep rebounds and represents a higher percentage of total sleep time than before alcohol consumption began. As a result, individuals sleep poorly and experience nightmares.

Effects on Pregnancy
The consumption of alcohol during pregnancy, even in moderation, greatly increases the risk of retardation in the development of the fetus (a very serious condition called fetal alcohol syndrome, and reducing the incidence of this behavior has been a major public health objective since the mid-1990s. From data averaged over 2007 and 2008, it has been estimated that about 11 percent of pregnant women consume alcohol, exposing approximately one in nine fetuses
to alcohol in utero. National public health goals for the United States in 2010 have included reducing this percentage to 6 percent. In an effort to attain this objective, brief interventions to help pregnant women achieve abstinence from alcohol have been developed. In one program of this kind, women were five times more likely to have abstained by the third trimester of pregnancy, relative to controls, after a 10–15 minute counseling session in a walk-in center.

Interactions with Other Drugs
A major concern in alcohol drinking is the complex interaction of alcohol with many drugs. As noted in Chapter 2, the DAWN reports of emergency department admissions and deaths show an extremely high incidence of medical crises arising from the combination of alcohol not only with prescribed medications but also with virtually all the illicit drugs on the street. Opiates and opiate-like drugs, marijuana, and many prescription medicines interact with alcohol such that the
resulting combination produces effects that are either the sum of the parts or greater than the sum of the parts.

In other cases, the ingestion of medications with alcohol significantly lessens the medication's benefits. Anticoagulants, ant