addictions > facts-about-alcohol

effect is not experienced immediately. The first effect lasts for two to three hours and starts to decrease as blood-alcohol levels start to fall. The second effect lasts for about twelve hours. This means that you can’t take a drink without an agitating effect that wears off slowly so that you end up more tense than you began. If someone has been drinking heavily it may take days for his/her psychomotor activity to return to normal. He/she will be anxious, shaking, sweating, restless. This accounts for hangovers, withdrawal symptoms and eventually delirium tremens (DTs) where the individual is so agitated and anxious that he is in a state of terror and may even get convulsions.

The effects of alcohol are not all reversible.

Brain cells once destroyed, cannot regenerate themselves. When enough of the brain is damaged, there are irreversible changes in a person’s behaviour and psychological status.
Alcohol affects the stomach. It is an irritant and causes loss of appetite, disturbed digestion, impaired absorption and vomiting. It can irritate the stomach lining leading to ulcers or chronic inflammation
In cases of excessive drinking, fat accumulates in the liver, impairing functioning, and where there is consistent damage, cirrhosis of the liver occurs with parts of the liver dying and being replaced by scar tissue
Heavy alcohol use is a leading cause of heart disease and circulatory disorders.
One of the greatest causes of death in young people are accidents occurring after drinking.

(published with permission in writing from:http://addiction.ie)