Brian Byrne, a tour manager in Los Angeles, was sipping a cold brew a few years ago when he started feeling clammy. Soon, his symptoms worsened: shallow breathing, a hollow feeling in his chest and a rapid, thumping heartbeat. He went outside to get air. “At that point, I was having racing thoughts, feeling like I was having a heart attack,” he said.
This wasn’t the first time Mr. Byrne experienced a caffeine-fueled panic attack, but it was the most intense. “Drinking that coffee felt like I poured gasoline on a fire that was already smoldering,” he said. For a year after, he didn’t touch the stuff and didn’t have another serious episode.
Many people can relate to Mr. Byrne’s caffeine-related anxiety. While researchers can’t definitively say that caffeine makes you anxious, it’s linked to increased risk of anxiety among people with and without psychiatric diagnoses.
Why caffeine might make you anxious
Caffeine is a stimulant that affects the sympathetic nervous system — the part of the body responsible for your fight-or-flight response. When it’s activated, your heart rate rises and blood pressure goes up, your muscles tense, and you may start sweating.
But caffeine isn’t the only thing that arouses the nervous system. Any adrenaline-pumping activity — like exercising or riding a roller coaster — can stimulate a response.
When you’re working out or on a ride, those sensations aren’t a surprise. But the incongruity of sitting quietly at your desk while your heart is pounding, the way it might if you’ve just had some caffeine, can make some people experience that arousal as anxiety, said Joseph Trunzo, a deputy director of the School of Health and Behavioral Sciences at Bryant University. On top of that, if you subconsciously label these symptoms as anxiety, you might reinforce the effect.
Other factors can come into play, too. Caffeine acts against the brain chemical adenosine, which slows the heart rate and promotes drowsiness and relaxation. “When we ingest caffeine and it blocks those receptors, adenosine can’t do its job,” Dr. Trunzo said. Some scientists have speculated that the blocking of adenosine receptors might contribute to increased anxiety.
Caffeine can also disrupt sleep, particularly deep sleep, which helps keep anxiety at bay, said Dr. Sheenie Ambardar, a physician specializing in adult psychiatry in Beverly Hills, Calif. If the coffee is consumed within eight and a half hours of bedtime, caffeine might cause you to toss and turn, reducing the time you spend in deep sleep. Even slight disruptions in your sleep can increase anxiety levels the next day.
Caffeine affects everyone differently. If even a small amount of caffeine makes you anxious, you might have a certain genetic variant that influences how you metabolize caffeine, said Lina Begdache, a dietitian and associate professor of health and wellness studies at the State University of New York at Binghamton. In this case, you will process the caffeine more slowly, so it stays in the system longer and accumulates, potentially causing a more pronounced effect.
Managing anxiety in the moment
There’s no way to flush caffeine through your system quickly, but you can take steps to manage the anxiety if it strikes. Exercise may help distract you and reduce short-term symptoms.
You could also take a less physical approach: sitting with and acknowledging the sensations, instead of trying to fight them, said Avigail Lev, a licensed clinical psychologist in San Francisco. She suggests asking yourself questions like: Where in the body am I feeling this most intensely? Does it have a size or color? When you recognize that you can live with the feelings and are not in danger, they become much less debilitating.
Changing your relationship with caffeine
If you think your morning latte is making your heart race and palms sweat, there are ways to assess your intake.
Keep a log.
“I always encourage my patients to gather data,” said Dr. Ambardar, who suggested writing down how much caffeine you drink and how you feel for a month. Note your sources of caffeine and how much they contain. The Food and Drug Administration has cited 400 milligrams per day — about four or five cups of coffee — as a safe amount for adults. The American College of Obstetricians and Gynecologists recommends limiting caffeine intake to 200 milligrams for pregnant women.
Consider tapering.
“The best way to find out what role the substance plays in your life is to stop using it and see what happens,” Dr. Trunzo said.
A few years ago, Dr. Ambardar had a patient who was dealing with severe anxiety. He had a high-pressure job and was drinking caffeine around the clock. Over several weeks, he reduced his intake and felt much more at ease. “He was really surprised and said, if he had known that this was the cause, he would have cut it back much sooner,” she recalled.
You don’t need to go cold turkey, either. Instead, cut back slowly. If you drink four cups of coffee a day, “start really small, like three and a half cups of coffee, then half a cup of decaf,” Dr. Ambardar said. After two weeks, you could drop to three cups, and continue that pattern.
Make other lifestyle changes.
When you reduce your overall anxiety, you’ll be less susceptible to the effects of caffeine, Dr. Begdache said. During the year that Mr. Byrne, the tour manager, quit coffee, he started therapy and daily exercise. He now has added caffeine back in moderation.
You can also take steps to improve your energy so you’re less reliant on caffeine, Dr. Begdache said. “It’s really a combination of factors that help you feel more energetic,” she explained. So, prioritize sleeping and exercising, staying hydrated and eating a healthy diet. With these changes, you might find that your latte is a pleasant boost instead of a source of anxiety.
