Alcohol abuse affects the human body as a system; its effects on separate parts of the body cause overall damage since those separate parts ultimately work together to keep the body stable.
The most obvious consequence of alcohol abuse is brain damage- In the human brain, alcohol is said to burn neurons, while increasing the size of the neural ventricles. The hallucinogenic effect produced by too much drink is a result of how alcohol basically poisons the cells found in the frontal lobe, which is the emotional side of our brain. For this reason, you see people showing erratic behaviors ranging from excessively uninhibited conduct to bouts of crying and despair. Alcoholics who are hardcore prefer drinking to eating, which is another bad consequence of drinking too much; a lack of "neural nourishment" can lead to terrible mental disorders caused by a lack of essential vitamins and acids.
The second most dangerous effect is in the liver. Too much alcohol in our blood makes the job of the liver quite hard. The job of the liver is cleansing and purifying our blood. When alcohol is excessive, the liver can work against itself, or die out altogether as its own cells become defective. This causes a disease called Cirrhosis and, what is worse, liver cancer. Alcoholic hepatitis is also another consequence of it.
The stomach is affected as well because alcohol's acidity burns the stomach lining making us feel quite sick. Since alcohol metabolism happens quicker than food metabolism, then food in the stomach will take longer to empty and run its normal digestive course because alcohol is taking priority. This is why people vomit when they drink too much after they have eaten a meal. Moreover, alcohol dehydrates the body; when dehydration pairs up with vomiting, the body becomes even more dehydrated and the consequences worsen.
Nervous system- Alcohol is a depressant and thus slows down impulses causing a myriad of conditions as a result including
- erectile dysfunction
- coordination, memory, mood problems
- bad motor skills
- not feeling pain (while one is actually hurting and needing help)
- slow essential responses
- hallucinations, personality changes, violent behavior in some cases.
As with other digestive organs, the intestines also have a soft lining which becomes ulcerated when there is too much alcohol in the blood. This causes major digestive problems which would prevent the body from absorbing major needed vitamins, especially in the small intestine.
The human body has hundreds of internal processes that also become affected by alcohol abuse. The best place to look for information to add to this list (which is quite short in comparison), is the actual Al-Anon (Alcoholics Anonymous) page and in there they are quite comprehensive about the effects of alcohol. The link is included for your information as well as Enote's own resources on the effects of alcohol in the human body.