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The Effects of Alcohol

Alcohol that people drink is Ethanol, a product of the fermentation of fruit and grains. Alcohol affects all body systems because it is absorbed from the stomach into the bloodstream. Alcohol alters a person's perceptions, emotions, movement, vision and hearing. To find out more, please visit

The website BRAD 21 displays a chart that describes effects of alcohol based on Blood Alcohol Concentration. BAC refers to the ratio of alcohol to blood in the bloodstream. It can be measured by blood, breath or urine tests. Estimated BAC charts using gender, weight and number of drinks are available as well.


Effects at Specific B.A.C. Levels

The effects of alcohol intoxication are greatly influenced by individual variations among users. Some users may become intoxicated at a much lower Blood Alcohol Concentration (BAC) level than is shown.

0.02-0.03 BAC: No loss of coordination, slight euphoria and loss of shyness. Depressant effects are not apparent. Mildly relaxed and maybe a little lightheaded.

0.04-0.06 BAC: Feeling of well-being, relaxation, lower inhibitions, sensation of warmth. Euphoria. Some minor impairment of reasoning and memory, lowering of caution. Your behavior may become exaggerated and emotions intensified (Good emotions are better, bad emotions are worse).

0.07-0.09 BAC: Slight impairment of balance, speech, vision, reaction time and hearing. Euphoria. Judgment and self-control are reduced, and caution, reason and memory are impaired, .08 is legally impaired and it is illegal to drive at this level. You will probably believe that you are functioning better than you really are.

0.10-0.125 BAC: Significant impairment of motor coordination and loss of good judgment. Speech may be slurred; balance, vision, reaction time and hearing will be impaired. Euphoria.

0.13-0.15 BAC: Gross motor impairment and lack of physical control. Blurred vision and major loss of balance. Euphoria is reduced and dysphoria (anxiety, restlessness) is beginning to appear. Judgment and perception are severely impaired.

0.16-0.19 BAC: Dysphoria predominates, nausea may appear. The drinker has the appearance of a "sloppy drunk."

0.20 BAC: Felling dazed, confused or otherwise disoriented. May need help to stand or walk. If you injure yourself you may not feel the pain. Some people experience nausea and vomiting at this level. The gag reflex is impaired and you can choke if you do vomit. Blackouts are likely at this level so you may not remember what has happened.

0.25 BAC: All mental, physical and sensory functions are severely impaired. Increased risk of asphyxiation from choking on vomit and of seriously injuring yourself by falls or other accidents.

0.30 BAC: STUPOR. You have little comprehension of where you are. You may pass out suddenly and be difficult to awaken.

0.35 BAC: Coma is possible. This is the level of surgical anesthesia.

0.40 BAC and up: Onset of coma, and possible death due to respiratory arrest.


Elimination of Alcohol

Ninety-five percent of Alcohol is eliminated from the body through the liver. Although many factors may influence how quickly alcohol is metabolized, healthy people eliminate alcohol at an approximate rate of .5 oz per hour. Generally approximately one drink per hour.



A blackout is an amnesia-like period which is preceded by excessive drinking. It is not passing out or losing consciousness. The drinker will appear to be normal and able to function. However, afterwards the drinker will not remember periods of time during or after drinking. A blackout may a few minutes or several hours. Some drinkers may report not remembering how they returned to their room or remember conversations during the evening. The exact cause of blackouts is not known. The simple explanation is that alcohol disrupts the storing of information in long term memory. Most drinkers do not have blackouts. Blackouts are very serious and leave people very vulnerable to danger during this period.

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