Originally Posted by Zenofzin

One standard drink (which is considered any drink containing 14 grams of alcohol) will increase your BAC by a maximum of 0.02, based on your body size, gender, and other factors. Within about an hour, your blood alcohol concentration would be at almost zero. The problem usually comes when you drink at a faster rate or otherwise drink several alcoholic drinks at once (like taking several shots). Your liver cannot process alcohol that quickly, causing it to accumulate in your blood and leading to a higher BAC. For the average person, it only takes about three or four drinks in one hour to reach a BAC of 0.08.

“Given the general rule, if your blood alcohol content is at the limit of 0.08, it would go down to 0.065 after one hour. It would take roughly five hours and twenty minutes for your body to completely metabolize the alcohol and eliminate it from the body. That’s also why it can be dangerous to drink too late into the night. If you have a high enough BAC, you may still actually be drunk when you wake up, which can still be a real problem if you have to drive to work. Those who have been binge drinking can have alcohol in their systems for over 10 hours.

Breathalyzers can detect alcohol within 15 minutes of your first drink and can continue for as long as the alcohol is in your system. Coffee, cold showers, and “sleeping it off” will not sober you up”