Alcohol affects many different organ systems. According to "Harrison's Principles of Internal Medicine," more than one or two drinks a day have a toxic effect. Some effects appear after only a few drinks, others after years of heavy drinking. According to the Centers for Disease Control and Prevention, about 10 percent of adults in the United States are heavy drinkers as defined by having five or more drinks a day, at least 12 days a year.
The Nervous System
Acute ingestion of alcohol can lead to disrupted sleep and blackouts, which are episodes of amnesia. Chronic ingestion causes peripheral neuropathy, symptoms of which include numbness and unpleasant sensations in the arms and legs. According to "Harrison's Principles of Internal Medicine," 1 percent of alcoholics have diseased cerebellums, leading to unsteady gait and abnormal eye movements. Fifty percent of alcoholics have evidence of brain atrophy on brain scans.
Gastrointestinal Effects
Inflammation of the esophagus and stomach can lead to bleeding. Alcoholics are prone to tears in the junction between the stomach and esophagus, which can lead to vomiting blood. Pancreatitis is common. As noted in "Harrison's Principles of internal Medicine," alcoholics are three times more likely to develop pancreatitis than nonalcoholics. Alcohol causes fat to accumulate in the liver, eventually leading to hepatitis and cirrhosis.
Cardiovascular Effects
Heavy consumption of alcohol can lead to hypertension, coronary artery disease and cardiomyopathy, disease of the heart muscle itself. This can lead to heart failure and also potentially fatal arrhythmias. According to "Harrison's Principles of Internal Medicine," the risk for coronary artery disease is six times greater in alcoholics versus nonalcoholics.
Alcohol During Pregnancy
Alcohol and its metabolites cross the placenta and affect the growing embryo. Fetal alcohol syndrome is a serious condition that can include microcephaly, which is a smaller-than-normal brain, mental retardation, congenital heart defects, small teeth with poorly developed enamel and a distinctive facial appearance.
Other Effects
Alcoholic myopathy affects about 40 percent of alcoholics. Symptoms include muscle weakness. Skeletal effects include decreased bone density and an increased risk for fractures. Production of white blood cells decreases and their function is impaired. One possible result is a false negative tuberculosis test, meaning the patient has TB but has no skin reaction.
References
- Centers for Disease Control and Prevention: Health, United States 2009, page 289
- "Harrison's Principles of Internal Medicine"; Anthony Fauci et al.; 2008
