A typical hangover lasts about 18 hours on average, though it can stretch anywhere from 14 to 23 hours after you stop drinking. Symptoms usually begin around 8 hours after your last drink, peak at roughly 14 hours, and gradually fade from there. In some cases, particularly after very heavy drinking, symptoms can linger for 24 hours or longer.
How a Hangover Unfolds Hour by Hour
Hangover symptoms follow a surprisingly predictable arc. They start climbing once your blood alcohol level drops significantly and hit their worst point when it returns to near zero, which for most people means the morning after a night of drinking. That 14-hour mark after your last drink tends to be the roughest stretch: peak nausea, the worst headache, the deepest fatigue.
From there, symptoms gradually taper. Most people feel noticeably better by the 18- to 20-hour mark, though a lingering sense of tiredness or mild brain fog can hang around a bit longer. If you stopped drinking at midnight, expect the worst around 2 p.m. the next day, with meaningful relief arriving by early evening. A particularly heavy session can push full recovery past the 24-hour mark.
What’s Actually Happening in Your Body
Your liver breaks alcohol down into a toxic intermediate called acetaldehyde before converting it into harmless acetic acid. The hangover largely exists in that gap: acetaldehyde is irritating to your tissues and contributes directly to nausea, headache, and that general feeling of being poisoned. How quickly your body clears acetaldehyde determines a big part of how long you feel terrible.
But acetaldehyde isn’t the whole story. Alcohol also causes dehydration by increasing urine output, which accounts for the dry mouth, thirst, and dizziness. It can trigger low blood sugar by interfering with how your body handles glucose. And alcoholic drinks contain small amounts of methanol, a more toxic alcohol that your body processes slowly. Methanol breaks down into formaldehyde and formic acid, both of which add to the misery. These overlapping processes, each on its own timeline, are why hangovers feel like several bad things happening at once.
Why Some Hangovers Last Longer Than Others
What You Drank Matters
Dark liquors like bourbon, brandy, cognac, and red wine contain high levels of compounds called congeners, which are byproducts of fermentation. These include methanol and other chemicals that your body has to process separately from the alcohol itself, essentially giving your liver more work to do. Clear drinks like vodka, gin, white wine, and light beer contain far fewer congeners. Drinking the same amount of alcohol from bourbon versus vodka can produce a meaningfully worse and longer hangover, largely because of the extra methanol load in the darker spirit.
Your Age Changes the Equation
If hangovers seem worse than they used to be, they probably are. As you age, your body holds less water overall and eliminates alcohol more slowly. The same number of drinks produces a higher blood alcohol concentration in your 50s or 60s than it did in your 30s. That means more acetaldehyde building up, more time spent processing it, and a longer recovery window. The two beers that once felt like nothing can now produce a noticeable next-day effect.
Poor Sleep Extends Recovery
Alcohol disrupts sleep architecture even when it seems to knock you out. It suppresses the deeper, more restorative stages of sleep and tends to cause early waking as your body metabolizes the alcohol. This fragmented sleep compounds the fatigue, brain fog, and irritability of the hangover itself. You’re not just recovering from the alcohol; you’re also running on poor-quality rest, which makes every other symptom feel worse and last longer.
Genetics Play a Role
Some people metabolize acetaldehyde much more slowly due to genetic variation in the enzyme responsible for breaking it down. This is especially common in people of East Asian descent, who may carry a less active version of that enzyme. The result is a faster flush response, more intense symptoms, and a hangover that can feel disproportionate to the amount consumed. If you’ve always seemed to get worse hangovers than your friends after the same number of drinks, your enzyme activity is likely part of the reason.
What Actually Helps You Recover Faster
There’s no shortcut that neutralizes a hangover, but you can support the processes your body is already running. Rehydrating is the most straightforward step: water, electrolyte drinks, or broth help counteract the fluid loss. Eating something with carbohydrates can address the low blood sugar that contributes to shakiness and fatigue. Time and sleep do the heaviest lifting, since your liver clears alcohol at a fixed rate regardless of what else you do.
Pain relievers can take the edge off a headache, but avoid acetaminophen (Tylenol) while your liver is still processing alcohol, since both compete for the same metabolic pathway. Anti-nausea strategies like small bland meals or ginger can help if your stomach is unsettled. Beyond that, the most effective intervention is simply waiting it out, and drinking less next time.
When It Might Not Be a Hangover
A standard hangover is unpleasant but self-limiting. Alcohol poisoning is not. If someone is confused, vomiting repeatedly, having seizures, struggling to stay conscious, or cannot be woken up, that’s a medical emergency, not a bad hangover. These symptoms typically appear while someone is still intoxicated or shortly after they stop drinking, rather than the next morning.
If your hangover symptoms persist well beyond 24 hours, or if you notice tremors, extreme anxiety, or a rapid heartbeat as the alcohol wears off, those can be signs of alcohol withdrawal rather than a simple hangover. Withdrawal occurs in people whose bodies have adapted to regular heavy drinking, and it carries its own risks that go beyond next-day discomfort.