What to Know About Mixing Alcohol and Caffeine

Medically Reviewed by Kathleen M. Zelman, RD, LD, MPH on February 12, 2024
3 min read

There has long been speculation about the effects of mixing caffeine and alcohol. That could be drinking coffee to try and sober yourself up, or combining energy drinks with alcohol to keep you partying all night long.

Studies show that when caffeine and alcohol are mixed, the caffeine can hide the negative effects of alcohol. This may lead to less safe drinking than normal. 

Mixing caffeine and alcohol may also affect your heart and the chemicals in your brain that regulate sleep.

Mixing a high-caffeine energy drink and alcohol is popular among younger adults. But these drinks mask the alcohol’s effects, which can lead to dangerous over-drinking. When mixing alcohol with caffeine, you’re less likely to feel the effects alcohol has on your body. 

Studies so far have not determined how safe caffeinated alcoholic drinks are, mainly because of variations in caffeine and alcohol content in them. Since there are no standard volumes or ratios used when mixing caffeine and alcohol, it’s hard to determine what’s safe and what will have bad effects. 

Even in controlled settings, results are still inconclusive. People metabolize caffeine at different rates. Caffeine sensitivity and certain lifestyle habits also make the results inconclusive. 

But mixing caffeine and alcohol raises your blood pressure, which increases your risk for: 

  • Stroke
  • Heart attack
  • Heart disease

Another side effect of mixing alcohol and caffeine is that it can cause an irregular heartbeat (atrial fibrillation). If you have a heart condition, you should avoid combining the two. 

Caffeine and alcohol affect the body by also messing with your sleep pattern. An irregular sleep schedule can lead to other heart conditions. 

Even though soda has caffeine in it, the levels are very different from energy drinks. Some energy drinks can contain 27 mg to 164 mg of caffeine per serving. Most sodas typically have between 24 mg to 46 mg of caffeine per serving. 

Since sodas have a more consistent caffeine level than energy drinks, they may be safer to mix with alcohol. Sodas typically don’t have enough caffeine to wake you up like energy drinks. 

Understandably, you might think coffee and alcohol make a great combination because alcohol makes you drowsy and coffee wakes you up.

Since caffeine doesn’t affect how your liver processes alcohol, coffee won’t make you less drunk. Coffee can make you feel more alert, and may increase your reaction time, but it can’t reduce your breath or blood alcohol concentrations. 

The FDA warns against mixing alcohol and caffeine. There’s an increased risk of alcohol-related incidents when the two are combined.

Binge drinking. One study has shown that students who binge drank were twice as likely to mix alcohol and energy drinks than non-binge drinkers. In this study, people who mixed energy drinks with alcohol were likely to binge six or more drinks at a time. 

Caffeinated alcoholic drinks. These types of drinks are premixed and were popular in the 2000s. These drinks have alcohol, caffeine, and other stimulants in them. They typically had a higher alcohol content than beer and were primarily marketed to younger adults. In 2010, the FDA removed the caffeinated alcoholic beverages from the market.