Alcohol is a depressant: it slows the reactions of the central nervous system. When consuming alcohol, the main reaction takes place in the Liver, which metabolizes the alcohol to remove it from the body and bloodstream. Alcohol cannot be metabolized by the body directly, and it cannot be stored like Glucose.
The Liver can only process one ounce of alcohol every hour, so more consumption leads to a higher Blood Alcohol Level; this is where the alcohol stays until the Liver can process it. Effects can last for several hours. Only some of the alcohol is absorbed into the bloodstream in the Stomach; most is absorbed through the Small Intestine.
Because Alcohol stimulates Insulin production, increased drinking can be hazardous for diabetics, and it also stimulates production of urine and sweat, which can cause dehydration.