That nervous, uneasy feeling the day after drinking has a name — hangxiety. It affects an estimated 12% of drinkers regularly and up to 22% occasionally, according to a 2019 study published in Personality and Individual Differences. The biology is straightforward: alcohol enhances the effect of GABA, the brain's primary inhibitory neurotransmitter, producing feelings of calm and relaxation while you drink. Simultaneously, it suppresses glutamate, the main excitatory neurotransmitter. When alcohol wears off, your brain rebounds — GABA activity drops below baseline while glutamate surges above normal. This neurochemical imbalance produces anxiety, restlessness, and heightened stress sensitivity that can last 12–24 hours after your last drink. Cortisol also spikes during hangover recovery. A 2003 study in Alcohol and Alcoholism found that cortisol levels were significantly elevated the morning after heavy drinking, contributing to the "fight-or-flight" feeling many people experience. People with higher baseline anxiety or those who drink specifically to reduce social anxiety tend to experience worse hangxiety, creating a vicious cycle: you drink to ease anxiety, then experience worse anxiety the next day, which increases the temptation to drink again. What actually helps: time is the most reliable remedy, as your neurotransmitter balance normalizes within 24 hours. Hydration helps because dehydration worsens anxiety symptoms. Light exercise can boost endorphins and counteract cortisol. Importantly, "hair of the dog" — drinking more alcohol to ease hangover anxiety — only delays and worsens the rebound. Sources: Marsh et al. (2019) "Shyness, alcohol use, and hangover anxiety," Alcohol and Alcoholism (2003) cortisol and alcohol withdrawal studies, NIAAA.