Caffeine and Headaches: What's the Link?
Everyone gets headaches from time to time. And most of us have caffeine in something we drink or eat every day. Could there be a connection? There is, and it's a somewhat complicated one: It's possible for caffeine to either cause or help relieve a headache.
How Caffeine Helps Ease a Headache
When your head hurts, you want relief fast. Whether it’s a run-of-the-mill tension headache or a migraine, caffeine can often help. That’s why it’s an ingredient in a lot of popular pain relievers. It can make them as much as 40% more effective. Sometimes you can stop head pain in its tracks just by having caffeine.
So how does caffeine help with headaches? First of all, it helps reduce inflammation. When you have a headache, changes to your blood vessels lead to increased blood flow around your brain. This puts pressures on nerves in the area, leading to head pain. But caffeine narrows the blood vessels, which decreases the pressure and eases pain. This effect is stronger in people who use caffeine only once in awhile.
Caffeine gives a boost to common headache remedies in part by helping your body to absorb them. Whether you use aspirin, ibuprofen, or acetaminophen, they work faster and better and keep the pain away longer when combined with caffeine.
Caffeine also relieves headaches that are caused by caffeine withdrawal. That can happen when, for example, you usually drink coffee or tea in the morning and suddenly stop.
A very rare condition called hypnic headaches responds especially well to caffeine. These strike older people, waking them in the middle of the night with serious pain. Doctors may tell people who get these to have a cup of coffee before bed.
Caffeine Withdrawal Headaches
Oddly enough, the same thing that makes caffeine helpful for pain relief can also cause headaches. Since caffeine narrows the blood vessels that surround your brain, when you stop using it, they expand again. And that can cause pain.
It’s easy for your body to get so used to the effects of caffeine that when you cut back, you go into withdrawal. About half of people who withdraw from caffeine will get a headache. It most often affects people who've been taking in more than 20 milligrams of caffeine (the amount in about two 8-ounce cups of coffee) per day for at least 2 weeks. But it can happen when you regularly have any amount of caffeine, even as little as one cup of coffee a day.
You don't have to stop cold turkey to trigger a caffeine withdrawal headache. You can get one when the amount of caffeine you take in changes from day to day – or even if you have your daily cuppa a little later in the morning than usual.
How long do caffeine withdrawal headaches last?
Symptoms of withdrawal usually start 12 to 24 hours after you last have caffeine and can last up to 9 days (unless you start having caffeine again). Headache pain is usually at its worst 20-51 hours after you last have caffeine.
What do caffeine withdrawal headaches feel like?
The pain from a caffeine withdrawal headache tends to be throbbing or pulsing. Caffeine withdrawal may also cause:
- Nausea
- Muscle pain or weakness
- Fatigue or sleepiness
- Moodiness
- Trouble focusing
Other Caffeine Headaches
Withdrawal isn't the only way caffeine can cause headaches. It can also happen when you have:
Too much caffeine. Having more caffeine per day than you'd get in about four cups of coffee can also cause headaches. Some energy drinks could get you to this level in a hurry.
Caffeine sensitivity. Some people are naturally very sensitive to the effects of caffeine. Others become more sensitive to it as they get older and it takes longer for their bodies to metabolize it. That means you could drink the same amount of tea you've been drinking each morning for years and end up with a headache from caffeine overuse.
Medication overuse. Caffeine can also be a factor in what’s known as a medication overuse headache, or a rebound headache. This can happen when you take too much of any kind of pain reliever or take it too often. When the medicine wears off, your pain comes back worse than before. When you combine caffeine with pain relievers, this is more likely to happen.
Dehydration. Caffeine makes you pee more, which can lead to dehydration. Dehydration, in turn, can trigger a headache. This diuretic effect can also cause your body to lose magnesium, which can cause headaches, too.
Sleep loss. Lack of sleep can trigger a migraine attack, and caffeine may keep you from getting enough shut-eye. You can still have traces of caffeine in your system for up to a full day after consuming it.
Allergic reaction. It's rare, but some people can be allergic to caffeine. Symptoms can include headaches as well as a skin rash, breathing problems, and digestive issues like nausea or diarrhea. Even a small amount could trigger a reaction.
Caffeine and migraines
Many doctors recommend that people with migraines avoid caffeine. It's not clear exactly why caffeine, or foods and drinks that contain it, seem to trigger migraines in some people. But researchers do know that caffeine can block the effects of a chemical in your cells called adenosine. Adenosine causes blood vessels to expand, and levels of it in your blood increase during migraine attacks.
For people who get up to 14 migraine headaches a month, one to two servings of caffeine (150-200 milligrams) a day might help prevent headaches. But three servings or more could increase the number of attacks you have each month.
What You Can Do
It's important to be aware of how caffeine affects you, and pay attention to how much of it you drink and eat. To see if it might bring on your headaches, use a headache app or journal to look for possible triggers and keep track of what seems to help. Other tips include:
- Stay hydrated. For most people, this means drinking at least eight glasses of water a day. If you consume caffeine, add a full glass of water for each cup of coffee or tea you have. This will help make up for caffeine's dehydrating effects.
- If you consume caffeine, do it consistently. Try to have about the same amount around the same time each day to avoid a withdrawal headache.
- When you want to cut down on caffeine, do it gradually to reduce withdrawal symptoms. Try to cut your intake by 25% each week. For example, if you have two cups of coffee every morning, go down to 1½ cups the first week, then 1 cup, and so on.
- Don't forget about less obvious sources of caffeine, like decaffeinated coffee, green tea, some sodas, chocolate, and over-the- counter medications.
- While you're weaning yourself off of caffeine, get extra rest to help prevent withdrawal symptoms. Go to bed a little earlier, or take a nap during the day.
- You may be able to lessen head pain by using an ice pack on your head or rubbing peppermint oil into your temples, forehead, or neck.
- Try to manage stress. You might be able to beat a headache with relaxation techniques, meditation, or massage.
Takeaways
Caffeine can sometimes help a headache go away in the short term, but it can also cause headaches. Many things play a role in this, including how much caffeine you consume and your own tolerance level. A headache journal or app can help you be aware of how caffeine affects you and your headaches.
Caffeine Headaches FAQs
How do you fight a caffeine headache?
If you have a caffeine withdrawal headache, you may be able to ease it by taking these steps:
- Stay hydrated. For most people, that's about eight glasses of water a day.
- Get enough sleep. Most people need at least 7½ hours of shut-eye.
- Try stress busting-techniques. Meditation, yoga, or breathing exercises may help.
- Use pain relievers. Over-the-counter painkillers can help. If you're trying to cut out caffeine, make sure to choose a caffeine-free type.
Do caffeine headaches go away after drinking caffeine?
Consuming at least 100 milligrams of caffeine (a little more than one cup of coffee) can usually ease a caffeine headache and other symptoms of caffeine withdrawal within an hour.
How can I reduce my caffeine intake without getting a headache?
The best way to prevent a withdrawal headache is to cut down on caffeine gradually. Experts suggest reducing your intake by no more than 25% a week.
How much caffeine does it take to trigger a migraine?
For some people, any amount of caffeine can touch off a migraine. If you have migraine, some experts recommend having caffeine on fewer than 3 days a week.
Can caffeine cause migraine auras?
If you already have migraine with aura, caffeine could trigger an attack that includes aura (sensory disturbances that come with a headache). If you haven't had a migraine with aura, experts don't think caffeine makes it more likely.