Why Do Hangovers Cause Headaches?
By Devin Bohbrink
Updated on December 28, 2022

Why Do Hangovers Cause Headaches?

It happens as soon as you open your eyes. You wake up after happy hour and your head is absolutely throbbing. Reaching for the water on your night stand, you assume you’ll never recover. The hangover is here, and it brought the dreaded hangover headache. 

Popping some ibuprofen may dull the pain, but have you ever wondered why you get a hangover headache? Sometimes they feel different than a regular headache, and there’s a reason for that. Before your next big night out that involves sunglasses inside the next day, we’re going to discuss hangover headaches and the science behind them. 

What is a Headache?

First, let’s go over what a headache is. You probably know, but you may not know the science behind it.  Simply defined, a headache is pain or discomfort that you feel in the head or the face. Headaches can be throbbing, dull, or sharp pains. They come in all shapes and sizes. The location, pain intensity, and how often they happen can vary greatly. 

Think about the headaches you’ve had. Sometimes they’re throbbing, other times they lightly linger all day. They’re like snowflakes. They have probably all felt different in one way or another. There are several parts of the body that can cause headaches, such as:


  • Facial nerves 
  • Scalp nerves 
  • Blood vessels at the surface of the brain
  • Head, neck and shoulder muscles 

Headaches are extremely common. In fact, about 96% of people will experience a headache in their lifetime. There are two main categories that headaches fall into. 

Primary Headaches

Primary headaches are caused by over activity of pain-sensitive structures in your head. This is your typical headache that you’ll experience. They are not a symptom of underlying disease, so they’re not typically something to worry about. It’s just an annoying and painful thing to experience. They can also be caused by outside factors, including alcohol. Hangover headaches fall into the primary headache category, 

 Secondary Headaches 

Secondary headaches are a symptom of an underlying condition such as disease. Common causes are sinus infections, concussions and ear infections. They can also be caused by more serious problems and a doctor should be consulted. 

What Causes  a Hangover Headache?

All headaches are miserable, but the hangover headache is the last thing you need after a night out. It’s one of the most common hangover symptoms, and can keep you from going about your day. There are several factors that may cause a hangover headache. This is due to how alcohol affects the body. 


One of the most common causes of a hangover headache is dehydration. This is because alcohol contains ethanol, which is a natural diuretic. A diuretic makes your body lose water and salt at a faster pace than normal. You’ll also lose essential vitamins and minerals, causing an imbalance in the body. 


Vasodilation is when the blood vessels in your body widen. This allows blood to flow and lower your blood pressure. It’s one of the first things that happens when you drink alcohol. This can lead to headaches, as well as high blood pressure. 


Alcohol contains congeners, which are a byproduct of the fermentation process. Congeners may cause hangover symptoms such as headaches. They are also known for causing some of the most common hangover symptoms such as upset stomach, as well. 

How to Ease a Hangover Headache 

Now that we know what may be causing that headache, it’s time to ease your symptoms. As always, the only way to avoid hangover symptoms is to abstain from drinking entirely. There are, however, some things you can do to remedy a headache. 


Since alcohol is a diuretic, you’re going to lose a lot of fluids. Think about how once you start drinking you have to go to the bathroom more often. This can cause dehydration, which can lead to headaches. Alcohol does this because it suppresses the hormone vasopressin, which affects how the kidneys absorb water. 

So, rehydrating yourself the day after a night out could ease the symptoms of your throbbing headache. According to the National Headache Foundation, you can use rehydration solutions to rebalance the glucose and electrolytes in your body. 

Anti-Inflammatory OTC Painkillers

If your only hangover symptom is a headache, you could look to regular headache remedies. For instance, NSAIDs such as ibuprofen can reduce the inflammation causing a headache. Keep in mind that after a night of drinking, however, they may not be the best choice. They may make your liver go into overdrive, or irritate the lining of your stomach. 

Take Magnesium Supplements 

Have a hangover headache? Try popping a magnesium supplement. Research shows that magnesium can improve headache and migraine symptoms when taken. It’s a well tolerated and inexpensive option to keep in your medicine cabinet. If you have any health conditions, talk to your medical provider before introducing a new supplement. 

When to See a Doctor

It’s important to remember that your hangover headache could be caused by something else. If it doesn’t clear up after a day or with home remedies, call your doctor. You should also seek medical help if your headache is accompanied by: 

  • Excessive vomiting 
  • Chills 
  • Feeling focused 
  • Difficulty breathing 
  • Skin changing to a dark blue/purple color
  • Seizures 

Never be afraid to seek help if you need it, and it’s always better to be safe than sorry. 

Avoiding a Hangover Headache

Remember, if you don’t want to stop drinking entirely, you will inevitably end up with a hangover headache at some point. 

Pace Yourself

We’ve said it before, and we’ll say it again. Only you know your true limits when it comes to alcohol. Taking it easy and pacing yourself can help you avoid that splitting headache the next day. If you know that after three drinks you wake up feeling like garbage, try to only have two. 

Eat a Good Meal Before You Go Out 

When you drink on an empty stomach, alcohol absorbs into your bloodstream faster. Eating a decent meal before hitting the town can help slow down the absorption, thus potentially avoiding worse hangover symptoms. 

Stick to Light Colored Alcohol 

Remember the congeners we mentioned? Darker liquor will have a higher concentration of them. Sticking to lighter colored liquors can help you lower your risk of dealing with a hangover headache the next morning. 

Final Thoughts

The bottom line is that hangover headaches are always unpleasant. It can be caused by a number of factors, and there’s no way to avoid it completely. Sometimes you’ll have one, sometimes you won’t. Knowing your limits and eating a good meal before you go out can help you lessen the chance of having a hangover headache. 

As always, please drink responsibly and have fun! 


Devin Bohbrink

I'm a content writer from Chicago that loves her cocktails. Let's talk all things hangover, and how we can get rid of those nasty symptoms after a night out.

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