Two-thirds of American adults consume beverages containing ethanol (ethyl alcohol), and moderate ethanol intake appears to reduce the risk of myocardial infarction and other heart diseases. However, up to 10 percent of adults in the United States abuse ethanol, and acute ethanol intoxication is associated with a number of complications including traffic accidents, domestic violence, homicide, and suicide. Uncomplicated ethanol intoxication is estimated to be responsible for over 600,000 emergency department visits each year in the United States . (See "Cardiovascular benefits and risks of moderate alcohol consumption" and "Alcohol use disorder: Epidemiology, pathogenesis, clinical manifestations, adverse consequences, and diagnosis", section on 'Adverse consequences'.)
An overview of the pathophysiology, clinical features and management of acute ethanol intoxication in adults will be presented here. The health effects of chronic alcohol abuse, the recognition and management of alcohol withdrawal, and ethanol intoxication in children are discussed separately. (See "Management of moderate and severe alcohol withdrawal syndromes" and "Ethanol intoxication in children: Epidemiology, estimation of toxicity, and toxic effects".)
According to the Department of Health and Human Services and the United States Department of Agriculture, one standard drink contains approximately 0.5 ounces of ethanol . This corresponds to 12 fluid ounces of regular beer, 5 fluid ounces of wine, or 1.5 fluid ounces of 80-proof distilled spirit. Ethanol is also found in a variety of common household products, including mouthwash, perfume, cologne, cooking extracts, and over-the-counter medications.
Ethanol (CH3CH2OH) is a water-soluble alcohol that rapidly crosses cell membranes . Absorption of ethanol occurs via the gastrointestinal system, primarily in the stomach (70 percent) and duodenum (25 percent), with a small amount absorbed by the remaining intestine . When the stomach is empty, peak blood ethanol levels are reached between 30 and 90 minutes after ingestion.
The primary pathway of ethanol metabolism occurs in the liver via alcohol dehydrogenase . Although the majority of ethanol metabolism takes place in the liver, other tissues do contribute to alcohol metabolism. Alcohol dehydrogenase is also located in the gastric mucosa, but this gastric metabolism of alcohol is decreased in women. Decreased "first-pass metabolism", combined with a smaller volume of distribution, may explain the enhanced vulnerability of women to acute complications of alcohol intoxication . (See "Pathogenesis of alcoholic liver disease", section on 'Alcohol metabolism'.)