Never assume that going to bed means all of the alcohol leaves your system. You can still be drunk the next morning, and there are plenty of cases of people getting arrested on DUI charges even though they claim they haven’t had anything to drink that day. The issue is that they were still intoxicated when they woke up, but they got in the car — to head home or to go to work, for example — and drove anyway.

What you must remember is that your BAC falls at a set level, regardless of what you’re doing. It just takes time for alcohol to clear your system.

How long will it take? That depends on your gender, your weight and how many drinks you had. For instance, a 160-pound man who had four drinks will take six hours to get back to a BAC of zero. For a 160-pound woman who also had four drinks, it would take seven hours.

One thing to keep in mind is that people often underestimate exactly how many drinks they had. Did you just drink one beer? Well, a standard drink is one 12-ounce beer that is 5% alcohol by volume. If you had a craft beer that is 10% alcohol, that’s actually two drinks. Most wine is between 11%-15%, so drinking 12 ounces of it would be far over one drink and closer to three. Each shot is a drink, so taking two shots and chasing them with a beer, though it may only take a few seconds, already puts you at three drinks.

There is no cure for a high BAC, other than time. Eating a meal doesn’t make it drop faster. Drinking a cup of coffee makes you feel awake, but your BAC stays the same. Taking a shower make wake you up, but it doesn’t sober you up. Even sleeping only helps because of the time that passes.

If you do end up getting a DUI in the morning, it can feel shocking and confusing. You didn’t mean to do anything wrong. Be sure you know what defense options you have. You have to think about how charges like this may impact your future.