This article explains how environmental conditions and lifestyle factors during hot weather can cause headaches, as well as how to treat them.
How Hot Weather Causes Headaches
Dehydration
Many people look forward to the summer months, because they can engage in more activities and sports outside. But not drinking enough fluids in hot weather could leave you with a dehydration headache.
When you are dehydrated, you have fewer fluids in your body tissues and brain. Your brain tissues shrink and pull away from the skull, causing nerve pain. Drinking fluids will replace the lost tissue fluids to a normal level and eliminate the cause of headache pain.
Sun Exposure
In some cases, sun exposure can trigger a headache or migraine.
Photophobia is a term used to describe abnormal discomfort and sensitivity to light. It is a neurological symptom that involves the transmission of information between the eye and brain.
The part of the eye that transmits light to the brain is different than the part of the eye that provides vision. For this reason, even a blind person can develop a photophobia-induced headache.
Barometric Pressure
Barometric pressure is the air pressure level within the atmosphere. Summertime thunderstorms are one common cause of barometric pressure changes.
Research shows that even small decreases in atmospheric pressure can induce a migraine or headache.
Hormonal Changes
Hot flashes are associated with perimenopause and are caused by changes in estrogen levels. Estrogen works with a part of the brain involved in regulating body temperature.
Low estrogen can increase the body’s temperature to an uncomfortably hot level, causing hot flashes and night sweats.
Physical Activity
Headaches can be caused by physical activity when the weather is too hot, causing heat exhaustion.
Heat exhaustion occurs when the body gets too hot and cannot cool itself back down. This happens more commonly during warm and hot summer months, especially when humid.
Other symptoms of heat exhaustion include:
Dehydration Dizziness Muscle cramps Nausea and vomiting Heatstroke, which can be life-threatening
Heat Headache Symptoms
Headache symptoms may include:
Mild to moderate pain on both sides of the headHead pain that gets worse with activityConsistent pain that is dull but not throbbing
If your heat headache symptoms come with confusion, slurred speech, weakness, or numbness, call 911.
Heat Exhaustion Symptoms
Symptoms of heat exhaustion include:
Heavy sweatingCold, clammy skinTirednessWeaknessHeadacheFaintingDizzynessNausea and vomiting
If you start to experience heat exhaustion symptoms:
Sip waterMove to a cooler placeTake a cool bath or place cool compresses on your bodyTake off or loosen clothing
Treatment for Heat Headaches
One way to help prevent heat headaches is to drink plenty of water and take breaks from hot weather activity.
Once you realize you are getting a heat headache, take measures to help yourself so that symptoms don’t get worse:
Find a place to cool down and restDrink water for hydrationCall your healthcare provider if additional help is needed
Many headaches also respond to over-the-counter (OTC) pain medications, such as ibuprofen or acetaminophen. Talk with your healthcare provider before taking any new medicines.
When to Seek Medical Attention
If your symptoms don’t improve after about an hour of rest and fluids, call your healthcare provider.
Call 911 or go to the nearest emergency room if:
Your symptoms last an hour or longerYou develop even more severe headache painYou are vomitingYour symptoms continue to worsenYou experience a change in neurological functionYou become confused or weak
Coping With Excessive Heat
Sweltering weather can be a challenge. But as much as it can be uncomfortable, sometimes high temperatures cannot be avoided entirely.
If you cannot avoid heat, here are a few helpful ways to manage it:
Keep a water bottle with you and drink plenty of fluids. Check the forecast to prepare for hot weather. Keep headache medicine on hand. Wear lightweight and loose-fitting clothes. Stay with friends while in high heat in case someone needs help. Wear and reapply sunscreen regularly. Bring a sun umbrella. Sit in a pool or go swimming to cool off. Alter your schedule to avoid the heat.
Summary
Headaches can be a symptom of heat-related disorders, such as heat exhaustion. Although heat itself doesn’t cause headaches, it can cause circumstances which may lead to headaches, such as dehydration. Hot weather headaches can also be caused by sun exposure, barometric pressure, and physical activity.
If you have a heat headache, take measures to help yourself so that symptoms don’t get worse, like finding a place to cool down and rest, as well as drink water for hydration. You can also take OTC pain medications to relieve your head pain. Call your healthcare provider if additional help is needed.
If you develop extreme headache pain, a change in neurological function, or become confused, call 911 immediately.
A Word From Verywell
Having a heat-related headache can be a pain, but there are many things you can do to prevent and treat them. Experiment with proactive strategies to prevent getting a headache, and ask for support when you need it, especially if you will be out in hot weather for an extended period of time.
If you are prone to headaches, continue to educate yourself about potential triggers and have a management plan in case one arises. You may also want to consider keeping a “headache diary” to help you identify triggers and prevent future headaches from occurring.
Heat cramps (muscle spasms)Heat rash (painful and red skin irritation)Heat exhaustionHeatstroke (a life-threatening condition when the body reaches 106 F quickly)
Heavy sweatingCold, clammy skinTirednessWeaknessHeadacheFaintingDizziness
