Can You Still Be Drunk the Next Day?

Alcohol leaves your body at a fixed, surprisingly slow rate, and if you drink enough, your blood alcohol concentration can remain above the legal driving limit well into the following morning. The average person clears roughly 15 milligrams of alcohol per deciliter of blood per hour, which means a heavy night of drinking that pushes your blood alcohol to twice or three times the legal limit could leave you legally impaired eight or more hours later. But even after your blood alcohol has dropped to zero, the story is not over: research shows that hangover-related cognitive impairment can rival the effects of being at the legal limit itself.

How Fast Your Body Actually Clears Alcohol

Once your blood alcohol concentration climbs above a fairly low threshold, your liver’s main alcohol-processing enzyme becomes saturated. At that point, your body can only burn through alcohol at a steady, clock-like pace regardless of how much is still circulating. For moderate drinkers, that rate averages about 15 mg per 100 mL of blood per hour, though it can range anywhere from 10 to 35 mg per 100 mL per hour depending on the person.¹

To put that in practical terms, the legal blood alcohol limit for driving in most U.S. states is 80 mg per 100 mL (0.08%). If a night of drinking pushes your blood alcohol to around 200 mg per 100 mL, which is not unusual after a heavy session of binge drinking, you would need roughly eight hours at the average clearance rate just to get back to the legal limit. If your personal clearance rate is on the slow end, you could be looking at twelve hours or longer. Someone who stops drinking at 2 a.m. after reaching that level might still be over the legal limit at 10 a.m.

Several things influence how quickly you reach a high blood alcohol level in the first place. Drinking on an empty stomach lets alcohol absorb faster because there is nothing slowing it down in the gut. Solid food delays gastric emptying more effectively than liquids, which is why the old advice to eat a proper meal before drinking has some real pharmacological backing.² A faster rise to a higher peak means a longer wait the next morning before your body has fully cleared the alcohol.

Hangover Impairment Can Be as Bad as Being Drunk

Here is where things get counterintuitive. Even after your blood alcohol has fallen to zero, the morning after heavy drinking often leaves you performing as poorly on mental and physical tasks as you did while intoxicated. One study directly compared people’s performance during acute intoxication at the legal driving limit with their performance the following morning during hangover. Reaction time, divided attention, selective attention, and Stroop interference were all impaired to a comparable degree. On some tasks, including delayed recognition and certain reaction-time measures, hangover performance was actually worse than performance at the legal limit.³

These findings are not isolated. Research on hangover and executive function found that people in a hangover state recalled fewer items on verbal fluency tasks and performed worse on prospective memory, which is the ability to remember to do something you planned to do later.⁴ That kind of impairment matters for anyone who has to make decisions, drive, operate equipment, or simply remember their morning commitments.

A separate study looking at psychomotor vigilance the morning after drinking found that reaction times were significantly slower compared to placebo, and that hangover severity predicted how poorly participants performed. Even mild hangovers were associated with measurably slower responses.⁵ In that study, about a fifth of participants reported no hangover at all, yet the group as a whole still showed impaired vigilance, suggesting that even people who feel fine may not be performing at their best.

Why People Misjudge Their Ability to Drive

One of the most practically dangerous aspects of morning-after intoxication and hangover is how badly people assess their own fitness to drive. A study examining next-morning perceptions found that no participants mistakenly thought they were under the legal limit when they were actually over it. That sounds reassuring until you see the flip side: nearly half of participants believed they were over the limit when they were actually legally under it, and a fifth of those people who believed they were still over the limit rated themselves as safe to drive anyway.⁶

That disconnect reveals a troubling pattern. People use how they feel as a proxy for how impaired they are, but hangover symptoms and actual cognitive impairment do not line up neatly. You can feel terrible and be legally sober. You can also feel relatively fine and still be over the limit, or at least cognitively impaired enough that driving would be risky. The absence of a pounding headache does not mean your reaction time and attention are back to normal.

How Alcohol Wrecks Your Sleep and Makes the Morning Worse

Part of the reason the morning after feels so rough has nothing to do with residual alcohol in your blood and everything to do with what alcohol did to your sleep. A systematic review and meta-analysis of alcohol’s effects on sleep in healthy adults found a clear dose-response relationship: even a low dose of alcohol, roughly two standard drinks, delayed the onset of REM sleep and reduced its total duration. Higher doses made this disruption progressively worse.⁷

REM sleep is the stage most associated with memory consolidation and emotional regulation, and losing a chunk of it means you wake up with a cognitive deficit on top of whatever hangover physiology is happening. Alcohol also tends to produce a “rebound” effect in the second half of the night, where you wake more frequently once your body has metabolized enough alcohol to disrupt the sedative effect that helped you fall asleep in the first place. The result is a double hit: less restorative sleep overall, plus fragmented sleep in the hours before you wake up. That fatigue compounds whatever direct impairment the hangover itself is causing.

Individual Factors That Change the Timeline

The average elimination rate of about 15 mg per 100 mL per hour is just that, an average. Several factors push your personal rate higher or lower, and those differences can easily mean the difference between being sober by morning and still carrying a measurable blood alcohol level.

Genetics

Variants of the alcohol dehydrogenase genes, particularly ADH1B and ADH1C, produce enzymes that work at substantially different speeds. People carrying the ADH1B*2 or ADH1B*3 variants oxidize alcohol to acetaldehyde much more rapidly, while those with the ADH1C*2 variant have a slightly reduced capacity.⁸ These variants are distributed unevenly across populations, which is one reason the range of normal elimination rates is so wide. Two people of similar size drinking the same amount can have meaningfully different blood alcohol curves and wake up in very different states the next day.

Age

As you get older, the enzymes responsible for breaking down alcohol become less active. On top of that, body water volume decreases with age, which means the same amount of alcohol distributes into a smaller volume and produces a higher peak blood alcohol concentration.⁹ The practical upshot is that a 60-year-old drinking the same amount as their 30-year-old self will reach a higher peak blood alcohol level and take longer to clear it. People who notice they “can’t drink like they used to” are not imagining things; the biochemistry has genuinely shifted.

Sex Differences

Men and women eliminate roughly the same total amount of alcohol per unit of body weight per hour. However, women eliminate significantly more alcohol per unit of lean body mass per hour, which reflects differences in body composition rather than an inherently faster metabolism.¹⁰ Because women on average have a lower total body water volume relative to body weight, they tend to reach higher blood alcohol levels from the same number of drinks. A separate study looking at both age and sex found that alcohol elimination rate was higher in males than in females across age groups, with the difference partly explained by differences in lean body mass and liver volume.¹¹ For women, this means a given number of drinks is more likely to push blood alcohol to levels that persist into the following morning.

Time of Day

There is also evidence that when you drink matters, not just how much. A review of circadian influences on blood alcohol found that most evidence points to higher peak blood alcohol concentrations when people drink during the biological morning, when circadian alerting is low. Some studies also suggest slower elimination rates at that time.¹² This is more relevant for shift workers or people who drink at unusual hours than for the typical evening drinker, but it highlights that your body’s internal clock plays a role in how alcohol is processed.

What About Congeners and Drink Choice

A persistent belief holds that darker spirits give you worse hangovers than clear ones, and there is a grain of truth to it, but the effect is narrower than most people assume. A controlled study comparing bourbon (high in congeners, the fermentation byproducts that give dark spirits their color and flavor) with vodka (low in congeners) found that bourbon did produce worse subjective hangover severity. However, no effect of congeners was found on next-day neurocognitive performance.¹³ In other words, you might feel worse after bourbon, but your brain works about the same either way. And a separate study found that neither the type of alcoholic beverage nor participant characteristics predicted whether someone would get a hangover at all.¹⁴ The total amount of alcohol consumed matters far more than what you drank it in.

How Long Alcohol Shows Up on Tests

Even after your blood alcohol has returned to zero and your hangover has faded, your body still carries chemical evidence of drinking. Standard breath and blood tests only detect alcohol while it is actively circulating, but urine tests can look for metabolites that linger much longer. Ethyl glucuronide and ethyl sulfate are conjugated metabolites of ethanol that are excreted in urine for a prolonged period compared to alcohol itself.¹⁵ These can remain detectable for roughly 24 to 80 hours after the last drink, depending on how much was consumed.

These markers are increasingly used in clinical settings, court-ordered monitoring, and workplace testing. Research has confirmed their value as reliable indicators of recent drinking, both for detecting heavy drinking episodes and as objective outcome measures in alcohol treatment programs.¹⁶ If you are subject to any kind of alcohol monitoring, the relevant question is not whether you are still drunk the next day but whether your body has finished producing and excreting these metabolites, which takes substantially longer than clearing the alcohol itself. Studies support the appropriateness of ethyl glucuronide as a measure of recent heavy drinking, meaning even a single heavy session can flag positive a day or two later.¹⁷

When “Sleeping It Off” Is Not Enough

The common strategy of going to sleep and assuming you will be fine by morning works only if the math adds up, and most people do not bother to run the numbers. If you stop drinking at midnight with a blood alcohol concentration of 0.20%, a reasonable estimate for a heavy night out, an average elimination rate of 0.015% per hour gets you to zero at about 1:15 p.m. the following day. That is more than thirteen hours. If you need to drive to work at 8 a.m., you would still be at roughly 0.08%, the legal limit itself.

The problem is compounded by the fact that people tend to underestimate both how much they drank and how high their peak blood alcohol actually reached. There is no reliable way to feel your blood alcohol concentration dropping. You go to sleep feeling very drunk, and you wake up feeling groggy and hungover, and the subjective shift from “still drunk” to “just hungover” is not something most people can identify with any precision. The safest assumption after a heavy night is that you should not be driving, operating machinery, or making important decisions early the next morning, even if you technically feel awake and functional.

None of this means every night out leaves you impaired the next day. If you had two or three drinks over several hours with dinner and stopped by 10 p.m., a normal elimination rate would likely clear the alcohol by midnight or shortly after. The risk concentrates around genuinely heavy drinking sessions, binge drinking, drinking late into the night, and situations where any of the individual factors discussed above tilt the math against you. The answer to the title question is not always yes, but it is yes more often than most people realize.