Most hangovers last between 12 and 24 hours, though some can stretch beyond that depending on how much you drank and several individual factors. Symptoms typically begin six to eight hours after your last drink and peak once your body has fully processed the alcohol. From there, you’re on a slow climb back to normal.
When Symptoms Start and Peak
A hangover doesn’t hit while you’re still drinking. It arrives once your blood alcohol level drops significantly, usually six to eight hours after you stop. That’s why you might feel fine going to bed and wake up miserable. The worst point comes when your blood alcohol concentration reaches zero, meaning your body has finished breaking down the ethanol but is still dealing with the aftermath.
For most people, this peak happens the morning after a night of heavy drinking. If you stopped drinking at midnight, you might feel the worst symptoms between 6 and 10 a.m., depending on how much you consumed. From that peak, symptoms gradually ease over the next several hours.
The Typical Timeline
Cleveland Clinic puts the standard window at eight to 24 hours from onset to resolution. That means if your hangover kicks in around 6 a.m., you can generally expect to feel better by the evening, with the worst of it concentrated in the morning and early afternoon. The NIAAA notes that symptoms can last 24 hours or longer in some cases.
Here’s roughly what to expect:
- Hours 0–4 after waking: Peak misery. Headache, nausea, fatigue, and sensitivity to light and sound are at their strongest.
- Hours 4–8: Symptoms begin to ease. Nausea often fades first, though fatigue and brain fog tend to linger.
- Hours 8–24: Most people feel significantly better, though mild tiredness or a dull headache can persist into the evening.
Why Some Hangovers Last Longer
Not all hangovers follow the same clock. Several factors push recovery well past the 24-hour mark.
How much you drank is the most obvious variable. The more alcohol your body has to process, the longer your blood alcohol takes to reach zero, and the longer the recovery window after that.
What you drank matters too. Darker spirits like bourbon and whiskey contain higher levels of congeners, which are chemical byproducts of fermentation. Research comparing bourbon and vodka drinkers found that bourbon, a high-congener liquor, produced noticeably more severe hangovers than vodka, which contains very few congeners. So a night of whiskey is more likely to leave you hurting the next day than the same amount of clear spirits.
Your genetics play a role that’s easy to underestimate. Your body breaks down alcohol in two steps: first into a toxic intermediate compound, then into something harmless. Some people, particularly those of East Asian descent, carry a gene variant that slows down that second step. The toxic intermediate builds up, causing facial flushing, nausea, and a greater risk of prolonged hangover symptoms. If you’ve ever turned red after a single drink, this enzyme difference is likely why.
Your age changes the equation over time. As you get older, your total body water volume decreases and your body eliminates alcohol more slowly. Harvard Health notes that the same two beers you handled easily in your 30s will produce a higher blood alcohol concentration in your 60s. That translates directly into longer, rougher hangovers as the decades pass.
Sleep, hydration, and food all influence how you feel during recovery. Alcohol disrupts sleep quality even if you’re unconscious for eight hours, and dehydration compounds the headache and fatigue. Drinking on an empty stomach accelerates alcohol absorption, which can intensify the hangover that follows.
What Actually Helps Recovery
Time is the only reliable cure. The Mayo Clinic is blunt about this: no natural remedy has been shown to consistently or effectively improve hangover symptoms in clinical studies. The supplements, IV drips, and “hangover cure” products marketed online haven’t held up under testing.
That said, you can make the wait more comfortable. Water and electrolyte drinks help counter dehydration. Simple, bland food gives your body fuel without upsetting your stomach further. Sleep, if you can get more of it, lets your body do repair work. Over-the-counter pain relievers can take the edge off a headache, though aspirin and ibuprofen can irritate an already sensitive stomach, and acetaminophen combined with residual alcohol is hard on your liver.
The “hair of the dog” approach (drinking more alcohol to ease symptoms) delays the hangover rather than curing it. You’re simply resetting the clock and will have to face the comedown eventually, often worse than if you’d just ridden it out.
When a Hangover Isn’t Just a Hangover
Most hangovers, even brutal ones, resolve within a day. If your symptoms last significantly beyond 48 hours, or if they include confusion, seizures, repeated vomiting that prevents you from keeping fluids down, or a very slow or irregular heartbeat, that’s beyond normal hangover territory. Severe alcohol poisoning and withdrawal share some symptoms with a bad hangover but require medical attention. The distinction matters most for people who drink heavily and regularly, where withdrawal symptoms can begin within hours of the last drink and escalate rather than improve.