Within 5-10 minutes the alcohol is absorbed directly into the blood stream from the stomach and upper part of the bowel (small intestine).
Alcohol dilates or widens the blood vessels as it enters the bloodstream causing:
- Greater flow of blood to the skin surface (blushing)
- Temporary feeling of warmth
- Increased heat loss and rapid body temperature decrease
- Drop in blood pressure.
The blood alcohol concentration (BAC) is the amount of alcohol in the blood at any given time.
At a BAC of 0.02% to 0.03%, people often feel very relaxed.
At a BAC of 0.04% to 0.05%, judgement, speech and motor coordination are definitely affected.
With a BAC of 0.08% to 0.10%, reflexes and judgement are clearly impaired.
0.2% BAC could result in unconsciousness, 0.3% could result in a coma, and a level of 0.4% to 0.5% could cause death through the suppression of the brain's breathing centre, the cerebellum.
The BAC increases when the body absorbs alcohol faster than it can eliminate it. So, because the body can only eliminate about one unit of alcohol per hour, drinking several drinks in an hour will increase the BAC much more than having one drink over a period of an hour or more.
Given the same amount of alcohol, and proportional to body weight, females will generally have a higher blood alcohol concentration than their male counterparts, due to less body fluids to dilute the alcohol and also to more body fat.
Women also produce less of the enzyme dehydrogenase which may help to partially explain why women become more intoxicated on less alcohol than men.