But there are other times when the effects of alcohol are absolutely not welcome. Maybe you want to drive home or perhaps the alcohol you drank has left you feeling nauseated. In moments like these, the main question on your mind is likely how long it will be until the alcohol is no longer in your system. The answer to this—including how long after drinking alcohol that tests will indicate that it’s still in your body—is determined by many different factors.
Factors that Determine How Long Alcohol Stays in Your System
“In general, how much you drink, how fast you drink, if your stomach is empty when you drink, your biological sex, your body composition, if you are on certain medications and your genetics all affect your alcohol clearance rate,” says Dr. Kathleen Grant, Ph.D., a professor of behavioral neuroscience in the OHSU School of Medicine and chief of the division of neuroscience at the OHSU Oregon National Primate Research Center. As Dr. Grant says, both someone’s biological sex and body composition can affect how quickly alcohol is being absorbed in their bloodstream—and how long it stays there. Dr. Jenna Nikolaides, MD, an assistant professor of emergency medicine at Rush Medical College, says that women absorb more alcohol than men. This, she says, is because men have more of an enzyme called alcohol dehydrogenase (ADH). She explains that ADH lives in the stomach lining and chemically reacts to alcohol before it has a chance to enter the bloodstream. Since men have more of this enzyme than women, more alcohol reaches women’s bloodstream than men’s. Interestingly, women metabolize alcohol faster than men as well. Also, people who have less fat metabolize alcohol faster than someone with more fat. In addition to all of this, Dr. Nikolaides says that some people metabolize alcohol faster than others due to genetics. What you drink, how much you consume and how fast you drink are all factors in how long alcohol stays in your system. While Dr. Nikolaides says that the type of alcohol that’s consumed doesn’t affect how long it will be in your body, how much alcohol is in your drink does play a role. If your drink is carbonated matters too. “Carbonated beverages containing alcohol reach higher blood levels faster than non-carbonated drinks,” Dr. Grant says. This means that alcoholic drinks that aren’t carbonated stay in the body longer than ones that are carbonated. Both experts say that whether or not you are drinking on an empty stomach matters as well. Both say that food slows down the metabolization of alcohol.
How Long Does Alcohol Stay in the Body?
It’s clear that a lot of factors determine how long alcohol stays in the body. But in general, both say that someone metabolizes one alcoholic drink per hour. However, Dr. Nikolaides says the time frame can be stretched to up to six hours, depending on the factors highlighted above. “We tend to clear our bloodstream of alcohol in a predictable way, usually around 0.02 grams per milliliter an hour. The legal limit is 0.08 grams per milliliter,” Dr. Nikolaides says. In terms of how long after drinking alcohol it will show up in a blood, urine or breath test, Dr. Nikolaides says that in urine, you can test for alcohol and its metabolites for about one to two days. Alcohol can be detected by a breathalyzer up to 24 hours after drinking alcohol. Blood tests have the shortest window, able to detect alcohol in the body up to 12 hours after drinking. “The legal limit for driving is 0.08%; this is also a definition for intoxication,” says Dr. Grant. If any test determines your blood-alcohol level is higher than this, it is not only unsafe to drive, it’s against the law. If you aren’t sure what your blood alcohol level is and are debating whether or not you should drive home, err on the side of safety and find an alternative way home; it just might save your life or someone else’s. The safest way to consume alcohol is in moderation, sipped slowly and with food. If you want to avoid a nasty hangover the morning after, it’s a formula worth sticking to. It’s a piece of wisdom you don’t need a breathalyzer to clue you in on. Next up, find out what it means to be sober curious.
Sources
Dr. Kathleen Grant, Ph.D., professor of behavioral neuroscience in the OHSU School of Medicine and chief of the division of neuroscience at the OHSU Oregon National Primate Research CenterDr. Jenna Nikolaides, MD, an assistant professor of emergency medicine at Rush Medical College
