When John McGeary leads therapy sessions for anxiety at the Veteran Affairs Medical Center in Providence, Rhode Island, he’ll often draw a graph on the board. It will show a diagonal line extending upward to signify increasing levels of anxiety. Halfway up, next to the label “drinking,” the line will nosedive to the bottom of the figure, representing the relief alcohol provides from those anxious thoughts.
McGeary, a psychologist who studies addiction at Brown University, will then trace the pattern—from the peak, down and back along the base of the graph, again and again, creating a messy triangle that signifies a messy cycle of dependence linking alcohol to anxiety. It’s a metaphor that resonates with many of his patients, he says. “They say, ‘Oh my god, that’s exactly why I drink’.”
Many people learn eventually that, while having a few drinks can delay or reduce anxiety in the moment, it can also create a sort of echo chamber effect—heightening those feelings the following day and in the days after. As George Koob, the director of the National Institute on Alcohol Abuse and Alcoholism, puts it, “There’s no free ride in the brain. You have to pay for everything eventually.”
It’s worth noting that this side-effect doesn’t hold true for everyone: Anxiety is not among the primary side-effects associated with a night of heavy drinking. In one study looking at the hangover symptoms of more than a thousand Dutch students, anxiety actually fell near bottom of the list, reported by only 7 percent of drinkers. The most common side effect was fatigue, listed by almost every student.
But for people who are predisposed to anxiety, there are several reasons this kind of feedback loop could occur—and fatigue is part of it. For one thing, excessive drinking disrupts normal sleep patterns and can leave you exhausted, and a sleep-deprived brain is less adept at shutting down anxiety and other negative thoughts, Koob says. Even though you crash in the first part of the night, the quality of your sleep is much worse. Alcohol also messes with a hormone in your kidneys so your body is more apt to flush water out than reabsorb liquids, which means you’re more likely to wake up to use the bathroom—and wind up dehydrated.
Aside from the disruption, your sleep isn’t as deep as it is when you’re sober. Alcohol rattles your normal sleep patterns, altering how long you spend in each stage of sleep, says Nasir Naqvi, a Columbia University psychiatrist and cognitive neuroscientist. In the first half of the night, alcohol suppresses rapid eye movement sleep, known as REM sleep, thought to be important for memory formation. As the effects of alcohol wears off, your body spends less time in its deepest stages of sleep, leaving you sluggish the next day.
“Your brain is generally on the fritz when you drank heavily the day before,” Naqvi says. The part of your brain largely responsible for shutting down worrying thoughts, the prefrontal cortex, is especially sensitive to this inadequate rest, McGeary says. This means drinking can exacerbate anxiety for those already disposed to the symptoms.
Furthermore, changes in sleep patterns can last for weeks, Naqvi says, diminishing the restorative function of sleep even after you’ve stopped drinking. For people who struggle with an alcohol use disorder, overcoming that lingering insomnia without resorting to drinking is often one of the greatest challenges for people trying to quit, he adds. For chronic, heavy drinkers, alcohol withdrawal can also induce anxiety by altering the brain’s chemical messaging system that helps keep you calm.
“If you take enough of something that is suppressing brain activity, systems are going to respond to try to return you to a functional state,” Koob says. A brain repeatedly inundated with a flood of alcohol, he explains, will produce fewer receptors of a neurotransmitter called gamma-aminobutyric acid, or GABA, which slows down neural activity.
Long after your body has processed the alcohol, your nervous system still operates with fewer GABA receptors. “That system that has been engaged to compensate is still there—and it takes a while for it to get back to normal.” A brain that is deficient in GABA receptors is essentially operating in overdrive, leaving you more prone to worrying thoughts, Koob says.
That struggle may be why so many people seem to agree with Johnny Cash, who once sang that the only cure for a hangover is to have another drink. That approach might work in the moment, but in fixing the problem, you only make it—and your anxiety—much worse.