2. Flowing Through Blood
After alcohol is absorbed it makes its way into the bloodstream. The circulatory system is fast, leading you to have a buzzed or drunk feeling. When alcohol is taken in faster than being released, BAC goes up. A breathalyzer tests the blood alcohol level coming from your lungs.
3. Liver's Work
Your liver starts to kick in to detoxify and metabolize the alcohol, which the efficiency doing so depends on how much you consumed, nutrition, heredity, etc. Two enzymes are involved in breaking down alcohol—alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH).
4. Result of Toxins
First alcohol is metabolized into acetaldehyde and then acetate, which then can easily be eliminated. However acetaldehyde, a highly toxic carcinogen, is a major culprit of hangovers. Your liver, stomach lining, and brain are not a fan, thus some of the feelings of nausea, vomiting, heartburn, and headaches.
5. Effects on Body
Although the bulk of alcohol metabolism is done in the liver, small amounts metabolizes in the pancreas, brain and gastrointestinal tract. This exposes those tissues to acetaldehyde’s damaging effects.
6. Pee Break
In an effort to aid the liver, the kidneys out the bladder, hence the reason for many pee breaks in a night. This is also what can make you dehydrated.
7. Brain Waves
Neurotransmitters in the brain, glutamate and GABA, are messed with by alcohol. This of course ties in with emotions, actions, and motor skills.
SOURCES:
https://www.scripps.edu/newsandviews/e_20020225/koob2.html
http://pubs.niaaa.nih.gov/publications/AA72/AA72.htm
http://www.mydr.com.au/gastrointestinal-health/liver-and-alcohol-breakdown
http://www.brown.edu/Student_Services/Health_Services/Health_Education/alcohol,_tobacco,_&_other_drugs/alcohol/alcohol_&_your_body.php
http://www.dummies.com/how-to/content/how-your-body-processes-alcohol.html
http://matterdome.com/post/2884-every-time-you-get-drunk-this-is-what-happens-to-your-body-and-your-brain/pages/1/
http://science.howstuffworks.com/life/inside-the-mind/human-brain/alcoholism3.htm