“Many of my patients with migraine see headaches pick up in the summer and find that their headaches can be worse after a full day of sun,” says Liza Smirnoff, MD, assistant professor of clinical neurology at The Miller School of Medicine at UHealth in Miami, Florida.
Here, learn why hot weather leads to headaches for some people, plus what to do if a heat-induced headache creeps up after a day spent in the sun.
Why does the heat give me a headache?
A headache from heat isn’t usually from the heat itself—it can be caused by a few related things, either on their own or in combination:
1. Dehydration
Being dehydrated can trigger a headache. Being out in the heat makes you sweat, which means you can become dehydrated more quickly than usual, especially if you forget to drink enough water, per Harvard Health Publishing. That’s especially true if you’re exercising or doing any kind of strenuous workout in the heat, Dr. Smirnoff points out.
2. Bright sun
Aside from making you sweat, intense sunlight can be really, y’know, bright. And that can be bad news if you’re prone to headaches.
“Many people with migraine are light-sensitive, so bright light can be a trigger for headaches,” Dr. Smirnoff says. While this isn’t necessarily a heat-related headache, it can still cause the same symptoms.
3. Air pressure changes
Any time the weather rapidly changes, the air pressure outside (AKA, the barometric pressure) can change, too, potentially triggering headaches. This change can happen when it goes from sunny to rainy or stormy really quickly, or if the outdoor temperature rises fast—especially on a very hot day, per the Mayo Clinic.
Are heat headaches dangerous?
By themselves, headaches triggered by the heat aren’t any more dangerous than headaches caused by other triggers. Problem is, heat headaches can sometimes be a warning sign of more serious heat-related problems. “It’s important to watch for a serious headache from heat exhaustion or heat stroke,” Dr. Smirnoff says.
Both heat exhaustion (where your body gets too hot and can’t cool itself) and heat stroke (a more severe form of heat exhaustion that requires emergency treatment) can give you a headache, but they’ll cause additional symptoms as well.
According to Johns Hopkins Medicine, a heat headache might:
- Cause head pain that slowly builds
- Hurt on one or both sides of your head
- Cause a dull pain, like your head is being squeezed
- Radiate down the back of your neck
- Be mild to moderate, but not severe
Other symptoms that go beyond your head could mean you’re dealing with something more serious, Dr. Smirnoff says. Very heavy sweating or completely dry skin, feeling faint, dizziness, fatigue, and muscle cramps are likely signs of heat exhaustion. Worsening symptoms like confusion, vomiting, rapid heart rate, heart palpitations with headache, trouble breathing, or even loss of consciousness could mean a heat stroke.
If you have any of the above symptoms or think you may be suffering from heat exhaustion or heat stroke, seek medical attention right away, as these conditions can be life-threatening.
How to get rid of a heat headache
As you turn to heat headache treatment, it’s important to not only treat your actual pain, but to stop the problem from turning into something more serious—like heat exhaustion or heat stroke. The best way to do that? Try the following tips:
- Chill out ASAP. First, get inside and cool off as quickly as you can, and hang out by the AC or a fan, Dr. Smirnoff recommends. If you can’t get inside, “cooling yourself down with a wet towel or ice packs applied to the armpits or neck can help,” she adds.
- Take small sips of cool water, the Mayo Clinic recommends. If you’ve got an electrolyte drink like Gatorade, that’ll help you rehydrate even faster, says Dr. Smirnoff.
- Put a cool compress on your head. It’ll do double duty easing your head pain and helping you cool off, says Dr. Smirnoff.
- Rest in a dark, quiet room. Stay away from bright light and bright noises, per The Migraine Trust.
- Take an over-the-counter (OTC) pain-reliever. Options like ibuprofen, naproxen, or acetaminophen can help relieve heat headache symptoms and other head and neck pain, per Michigan Medicine.
Prescription meds might also be an option if you get frequent headaches. Some of them can be taken at the first sign of pain, while others are meant to be taken daily as a preventive. You and your doctor can decide what’s best for you based on your symptoms and their severity.
How to prevent a heat headache
Know you’ll be spending a lot of time outside when it’s hot and sunny? Here are some key things you can do to keep a headache from coming on:
- Hydrate, and keep hydrating. “It’s important to hydrate before you go out into the sun,” Dr. Smirnoff says. Water or electrolyte drinks are good choices, as are water-rich fruits and veggies like watermelon, cucumbers, oranges, and berries. Once you’re outside, keep drinking. If you’re active, aim for around a cup of water every 15 to 20 minutes, per the Centers for Disease Control and Prevention (CDC). If you’re thirsty, chances are you’re already dehydrated. Avoid drinking alcohol, too, which can dehydrate you and trigger a headache.
- Shade your eyes. Wearing sunglasses, a hat, or both can “protect your eyes from bright light, which can help prevent head-induced headaches,” Dr. Smirnoff says.
- Avoid other triggers. If you know you tend to get a headache when you’re out on a hot day, go the extra mile to steer clear of other things that might make your head hurt. According to Mount Sinai, these can include alcohol, certain foods (especially processed red meats), smoking, sleep deprivation, slouching, physical exertion, or skipping meals.
When to see a doctor
If heat-related headaches (or headaches in general) are affecting your well being and interfering with your daily life, make an appointment to see your doctor. Together, you can talk through your symptoms and figure out the best treatment plan—which could include avoiding your triggers or taking prescription meds.
It’s also important to seek emergency medical care if you have signs of heat stroke or severe heat exhaustion. These all warrant a call to 911, per the CDC:
- Body temperature of 103 degrees Fahrenheit or higher
- Hot, red, dry skin
- Fast or weak pulse
- Severe headache
- Dizziness
- Nausea or vomiting
- Confusion
- Loss of consciousness
FAQ
Can you get a headache after running in the heat?
Both vigorous exercise and heat can trigger a headache. Put them together—like if you go for a run on a sweltering day—and you’ve got a potential double whammy for a headache on your hands. “When we exercise, we dehydrate a lot quicker and we lose electrolytes,” Dr. Smirnoff says. So if you’re planning to exercise outside on a hot day, make sure to hydrate well beforehand (a sports drink is better than water) and keep sipping throughout your workout, even if you aren’t thirsty, the Mayo Clinic recommends. Getting indoors and in cool air ASAP is another good heat headache relief strategy.
What are the first signs of heat exhaustion?
A headache can be an early sign of heat exhaustion, Dr. Smirnoff says. Per the CDC, other possible signs include heavy sweating, cold or clammy skin, pale skin, a fast or weak pulse, nausea or vomiting, muscle cramps, weakness or fatigue, dizziness, or faintness.
What can be mistaken for heat exhaustion?
Heat exhaustion and heat stroke are heat-related illnesses that share some symptom overlap, like a headache, rapid pulse, dizziness, and nausea or vomiting. But heat stroke symptoms are more severe and can quickly become life-threatening, per the Mayo Clinic. If you’re not sure what you or someone else is dealing with, play it safe and call 911.
