What Causes a Hangover?
Though other chemicals in your drink – or drinks – of choice contribute to your hangover, alcohol is the primary culprit. And it has many ways of making you miserable. Despite how often hangovers happen, little research exists to explain exactly why. Here’s what we do know about alcohol’s effects on the body and how it may bring on a hangover.
Immune response. Alcohol causes your immune system to release cytokines, which are proteins that help control inflammation in your body. Those cytokines appear to trigger many hangover symptoms, such as headache, fatigue, nausea, and more. They might even contribute to blacking out, or lapses in memory that can happen when you drink too much. They also may determine just how severe your hangover will be.
Inflammation. Part of your immune response to drinking alcohol, inflammation may cause some of your hangover symptoms, such as feeling generally unwell.
Dehydration. Alcohol disrupts communication between your brain and your kidneys. So, instead of retaining fluids the way you normally would, you have to pee more. That fluid loss leads to mild dehydration, which brings on symptoms like thirst, fatigue, and headache, which are common with hangovers. But the evidence that dehydration is truly linked to hangovers is lacking.
Stomach irritation. Alcohol makes your stomach produce more acid. It also prevents your stomach from emptying normally. The result: stomach pain, nausea, and vomiting.
Low blood sugar. When you drink, your body produces more lactic acid. That in turn curbs your body's production of blood sugar. When that happens, you may feel fatigued, shaky, sweaty, and hungry. This happens more often in people with alcohol use disorder.
Lost sleep. Alcohol is a sedative, so it may help you fall asleep quickly. But it also disrupts your sleep cycle. You get less deep, restorative sleep, so you wake up feeling poorly rested.
Blood vessel dilation. Alcohol causes your blood vessels to dilate, or widen. This process, called vasodilation, lowers your blood pressure temporarily. For some people, this can cause a headache, a common symptom of a hangover.
Congeners. Congeners are byproducts that are in alcoholic beverages as a result of distilling and fermenting. They contribute to the taste and smell of wine, liquor, and other alcoholic beverages. They also may make your hangover worse. This may be especially true if you drink dark liquors, like bourbon and brandy. They have more congeners than vodka, gin, and other clear alcohols.
Acetaldehyde in your body. When your liver breaks down the alcohol in your system, a toxic chemical called acetaldehyde gets produced. A rise in inflammation in many of your organs follows.
How Long Does a Hangover Last?
You likely want to know how to cure a hangover fast, but there’s only so much you can do to shorten how long you feel the symptoms of one.
You’ll start feeling the effects of a hangover hours after you stop drinking. Symptoms of a hangover can be mild or serious, depending on how much and what you drank. You’ll feel the worst as your blood alcohol level goes back to normal. Hangover symptoms can linger for a day or sometimes longer.
For almost as long as humans have had hangovers, we've tried to cure them with remedies that run the gamut, from vitamin B to pickle juice. Some hangover treatments work better than others, but none are an actual cure. The only way to avoid a hangover is to limit how much you drink or to not drink alcohol at all. And if you find that hangovers are affecting your work or relationships, talk to your doctor about your drinking.
That said, a few hangover remedies can bring you relief from at least some of your symptoms. Here are a few tips to try:
A big glass of water might be the easiest hangover solution. Alcohol dehydrates you by boosting the amount of urine your kidneys make. You also lose fluid when you sweat, vomit, or have diarrhea after a night of bingeing. And alcohol is a diuretic, which means it makes you pee a lot and lose a lot of liquid.Dehydration causes symptoms like a dry mouth and headache.
Drinking water also slows the rate at which your body absorbs alcohol and keeps your overall blood alcohol level lower.
If you drink alcohol, drink water before you go to bed. It will curb the effects of booze in the morning. It's also smart to keep a bottle of water by your bedside. Another drink of water when you wake up will help keep you hydrated. Have a sports drink to replace the sodium, potassium, and other electrolytes you've lost from vomiting or diarrhea.
Some people say that getting fluids through an IV can help ease hangover symptoms. This method has the informal name of "drip bar." It can be pricey, and health insurance doesn't cover the bill. But there's no need to pay for IV fluids when you can drink a glass of water for free. Getting an IV insertion increases your risk that a vein may clot or become inflamed, or the injection site could become infected.
Give yourself time and rest.
You can ease some of your hangover symptoms with a variety of remedies, but the only way to cure a hangover is to give it time to go away on its own. There’s a lot that your body has to do in order to feel better. It needs time to:
- Clear the toxins that were produced when your body broke down the alcohol you drank
- Heal the irritated tissue in your gut
- Return your immune system as well as your brain activity to normal
You should plan to make this time as restful as possible. Though you are no longer drunk, you won’t be at the top of your game as you recuperate, so take it easy.
Drink Korean pear juice.
While most over-the-counter hangover remedies won’t help much, there’s one supplement that may do you some good – but you'll have to plan ahead. Korean pear (Asian pear) juice is an old-school hangover remedy. Research shows that drinking about 7½ ounces helps lower blood alcohol levels and makes hangovers less intense. The catch is that you need to drink it before you have alcohol. Drinking it afterward won't work.
Researchers say Korean pears might work with your body's chemistry to break down alcohol faster. The extract has a protein that curbs the inflammation you can get from drinking too much. That may help hold off a hangover. Only a couple of studies have been done, which is far from proof that this hangover remedy works. But if you can find Korean pear juice at your local supermarket, it doesn't hurt to try a glass before you go out drinking.
This root has been a feature of Chinese medicine for thousands of years. Herbalists use it to treat everything from stress to asthma. In one small study, a drink made from red ginseng cut down hangover symptoms.
A different herb that goes by a similar name, Siberian ginseng extract, also improved hangover symptoms like headache, dizziness, and stomachache. But the Siberian type isn't the ginseng used in Chinese medicine.
Alcohol lowers your blood sugar. That may explain the dizziness and shaking some people get with a hangover. Your brain needs carbs for fuel. Have a couple of slices of wheat toast or a few whole-grain crackers to bring those blood sugar levels back up to normal. You'll give yourself an energy boost, too.
Take Phyllanthus amarus extract.
This medicinal herb grows along tropical coasts. It treats liver, kidney, and stomach illnesses. In one small study, taking Phyllanthus amarus extract twice a day for 10 days helped lower blood alcohol levels, ease hangover symptoms, and improve mood in regular drinkers.
You can find extracts made from this herb online and in health food stores. Some of these products go by the name "stone breaker" herb. That's because it may help lower your chances of getting kidney stones.
Take a pain reliever.
An over-the-counter (OTC) pain reliever will calm a pounding headache. Just be careful. They come with their own risks.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly available pain relievers that should help with your hangover headache. But they can irritate the lining of your stomach and worsen your nausea if you take more than the recommended dose. Common NSAIDs include:
- Naproxen sodium
Acetaminophen is another popular pain reliever. But it can damage your liver if you take it while you have alcohol in your system. It’s best to avoid it during a hangover.
Drink caffeine – in moderation.
If you don’t already drink coffee regularly, don’t down a cup in hopes of relieving your hangover. It may make things worse. Why? A few reasons.
Caffeine is a diuretic. That means you’ll pee more when you drink it. If you’re already dehydrated from your night out, your cup of coffee could make that worse by slowing down the rehydration process.
Caffeine can worsen headaches. Your morning cup temporarily narrows your blood vessels and increases your blood pressure. That’s a recipe for a worse headache than what you woke up with.
If coffee is part of your morning routine, go ahead and have a small cup. Otherwise, you risk a caffeine withdrawal headache.
Use caution before taking hangover supplements and vitamins.
Don’t get your hopes up that you’ll find a cure or preventive for your hangover in the supplements aisle. There’s very little research that shows supplements and vitamins help you feel better. Keep that warning in mind when shopping for any of the following examples:
B vitamins and zinc. In a small 2019 study, people whose diet contained more B vitamins and zinc had less severe hangovers.
Kamishoyosan (KSS). This traditional Japanese remedy includes ginger, brown sugar, and tangerine extract. It made hangovers less severe when taken before drinking alcohol, according to a 2010 Japanese study that included only 10 adults.
Some products marketed as hangover cures may be dangerous. They may contain unsafe amounts of vitamins and other ingredients. And they have not been evaluated by the FDA. In fact, the FDA has called out makers of so-called hangover cures for marketing unapproved concoctions. Use caution if you experiment with any anti-hangover supplements.
Beware the 'hair of the dog.'
The idea behind this popular hangover remedy is that taking another drink will ease the effects of the last few you had. The name comes from an old folk tale that says the way to treat a dog bite is to cover the wound with hair taken from the dog that bit you.
When you drink, alcohol holds back a brain chemical called glutamate. That causes your brain to make more and more of it. When the alcohol wears off, you have a bunch of it floating around in your brain. It may be to blame for hangover symptoms like crankiness, headaches, nausea, and fatigue.
Down another drink the next morning, and you'll hold off the glutamate all over again. Your hangover symptoms may improve. But it won't last. The truth is, drinking again will just throw your body back into the same destructive cycle without giving it time to heal. Experts don't suggest trying this method.
Don't light up and drink.
For some people, the two go together. But you may pay the price.
Studies show that if you smoke cigarettes while you drink, you may get a worse hangover. Researchers don't know why, but they think it may have to do with how nicotine works on your nervous system.
How to Cure Hangover Nausea
Feeling sick to your stomach is a hallmark hangover symptom. You can help your stomach feel better by eating bland foods that are high in carbohydrates. These include:
- Toast, like bagels and bread
It’s best to avoid greasy, heavy food, though you do want to eat a decent-sized breakfast to help restore your blood sugar level and relieve dehydration. To get more water into your system via breakfast, think fruits like watermelon, strawberries, and cantaloupe.
Speaking of water: Drinking water when you get up will help you rehydrate. But sip, don’t gulp. Flooding your stomach with water will only make it more upset. Also, drink room-temperature water. Ice water won’t be as gentle on your stomach. Sports drinks, coconut water, and electrolyte-infused drinks also help with hydration.
Sipping ginger tea or chewing on a bit of dried ginger may help relieve your nausea.
How to Cure Hangover Headache
Here are a few things to try to ease your aching head:
Nonsteroidal anti-inflammatory drugs (NSAIDs). Available over the counter, these painkillers will make your head feel better. They include:
- Naproxen sodium
Don’t reach for acetaminophen. It can damage your liver when mixed with alcohol.
Water. Dehydration can cause headaches, so drink some water. But go slowly so you don’t upset your stomach.
Carbs. Drinking lowers your blood sugar, which fuels your brain, and this could contribute to your headache. Carbohydrates in food can help boost your blood sugar back to normal. Try bland foods that are easy on your stomach, like toast and crackers, and drink some juice.
How to Cure a Hangover Fast
If only you could. There’s simply no cure other than time for a hangover. Figure you’ll feel bad for at least 8 hours and maybe a full 24 hours. That said, you can help yourself feel a bit better by doing the following:
Rehydrate with water or an electrolyte-rich sports drink. Drink slowly so you won’t further upset your stomach.
Take an OTC pain medication for your headache, such as ibuprofen or aspirin. But remember: Avoid acetaminophen (like Tylenol). It may cause liver damage if you still have alcohol in your system.
Eat. Food will help restore your blood sugar and can help you feel better. Eat crackers, toast, or other bland, carb-rich foods that are easy on your stomach.
Take a nap. Alcohol messes with your sleep, and that lack of rest leaves you fatigued.
There are a number of things that you can do to prevent or at least limit hangovers.
Drink less. Depending on how sensitive you are to alcohol, the only way to prevent a hangover may be to avoid drinking altogether. Some people have a hangover after a single drink. On the flipside, some people don’t get hungover no matter how much they drink. (If that's you, it doesn’t mean you should drink to excess!) So, if you don’t want a hangover, know your limits and don’t cross them.
Don’t drink on an empty stomach. You want food in your belly because it slows the absorption of alcohol into your system. Have a sizable meal before your evening out. This may tamp down the booze’s effects on your body.
Drink water. Drink a glass of water after every glass of beer or other alcoholic beverage you toss back. This will help you avoid dehydration. It also may keep you from overdoing it with the alcohol.
Slow your pace. Limit yourself to one drink per hour. That gives your body time to process the alcohol and may keep you from getting drunk. Going slow is especially important if you’re drinking sparkling wine or other carbonated alcoholic beverages. Those bubbles can boost the rate at which your body absorbs alcohol.
Steer clear of darker alcohols. Remember the congeners mentioned above? Bourbon, scotch, brandy, tequila, dark beers, and red wines contain large amounts of these chemical compounds, which cause more severe hangovers. Choose gin, vodka, light beer, or white wine instead. You’ll likely wake up feeling less miserable.
Hangovers are not inevitable if you drink. If you focus on moderation, stay hydrated, eat a healthy-sized meal, and drink slowly, you should be fine. But if you find yourself feeling miserable the next morning, drink some water, take an aspirin if you need one, crawl back into bed to catch up on sleep, and, above all, be patient. You’ll get better.
Hangover Cure FAQs
How do you make a hangover go away faster?
You can't. Time is the only cure. The best you can do is ease the symptoms somewhat and wait it out.
How do I stop feeling sick from a hangover?
Bland foods like toast and crackers, ginger tea, and sipping room-temperature water can help ease your upset stomach.
Can anything really help with a hangover?
A variety of remedies can help you feel a bit better, like over-the-counter pain medications for your headache and eating bland food to settle your stomach, but your hangover likely will be with you all day. Take a nap if you can to restore lost rest and to pass the time.
What drink helps with a hangover?
Water. It’s close at hand and helps relieve dehydration. You also can try electrolyte-rich sports drinks, juice, broth, and other liquids that your stomach can tolerate. Avoid drinking more alcohol.