YOU are out late at night and you’ve had one too many drinks. You’re feeling a bit inebriated, and you’re wondering if a cup of coffee can help.

Well, here’s the lowdown: While a cup of joe or shot of espresso can help to perk you up, it’s not going to help sober you up. In fact, in some situations, the combination of caffeine and alcohol could be potentially harmful.

“I call it the ‘perfect storm,’” said Dr. Mary Claire O’Brien, senior associate dean for health care education at the Wake Forest School of Medicine, who has researched the interactions between caffeine and alcohol, including its effects on injury risk.

Caffeine is a stimulant, so it can make you more alert and possibly improve your performance to some extent, according to Dr. Robert Swift, associate director of the Brown University Center for Alcohol and Addition Studies. Specifically, caffeine interferes with the action of a chemical known as adenosine. “Adenosine tends to be sedative ... and one of the signals to fall asleep is that adenosine builds up in the brain,” Swift said. By blocking the action of adenosine, caffeine has the ability to make you feel less tired, Swift explained.

Interestingly, alcohol can trigger the release of dopamine, which results in a stimulant effect when you first start drinking, though this does not necessarily mean you are any less impaired from alcohol, according to Swift.

Alcohol’s sedative effects tend to kick in after blood alcohol levels peak and then start to fall. Specifically, alcohol promotes the release of the brain chemical GABA, which produces sedation, Swift explained. Alcohol also blocks the action of glutamate, a brain chemical that stimulates nerve cells, and this blockade can also produce sedation. During this time, you might feel tired and in need of a pick-me-up.

Consuming caffeine might make you feel less sleepy when drinking alcohol, but it will not accelerate alcohol metabolism or ameliorate its effects, experts say. Mixing the two is also a practice that the U.S. Dietary Guidelines cautions against.

A major concern when seeking out coffee or any source of caffeine in an effort to feel awake after a few drinks is that by making you feel less tired, you may think you are less inebriated than you actually are.

“Even if someone feels like the caffeine causes them to feel more awake and less sluggish, they still need to be aware that the alcohol is still metabolizing in the same way and on the same timeframe as if they haven’t had any caffeine ... which means that its effects can still be potentially dangerous,” said Melissa Majumdar, a registered dietitian and spokesperson for the Academy of Nutrition and Dietetics.

Experts say the only way to sober up is to let time pass. The specific time it will take for alcohol to leave your system depends on the individual, but on average, people metabolize about one drink per hour. “If you’ve had five drinks, it would take about five hours to get the alcohol totally out of your system,” Swift said.

(SD-Agencies)