Alcohol moves very quickly into the blood without being broken down (metabolized) in your stomach. Within five minutes of having a drink, there's enough alcohol in your blood to measure. Thirty to 90 minutes after having a drink, the alcohol in your bloodstream is at its highest level.
Your liver does most of the job of breaking down the alcohol once it's in your body. But it needs time. If you weigh 150 pounds, it will take about 2 hours to metabolize a beer or mixed drink.
If you drink alcohol faster than your liver can break it down, the excess alcohol moves through your bloodstream to other parts of your body. Brain cells are easy targets. When someone talks about getting a buzz from alcohol, this is what they are feeling.