Brain & Nervous System Headaches Can Hot Weather Give You a Heat Headache? By Sarah Jividen, RN Sarah Jividen, RN Verywell Health's LinkedIn Sarah Jividen, RN, BSN, is a freelance healthcare journalist and content marketing writer at Health Writing Solutions, LLC. She has over a decade of direct patient care experience working as a registered nurse specializing in neurotrauma, stroke, and the emergency room. Learn about our editorial process Updated on May 19, 2023 Medically reviewed by Kashif J. Piracha, MD Medically reviewed by Kashif J. Piracha, MD Verywell Health's LinkedIn Kashif J. Piracha, MD, is a board-certified physician with over 14 years of experience treating patients in acute care hospitals and rehabilitation facilities. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Causes Symptoms Treatment When to Seek Help Coping Frequently Asked Questions Headache and migraine triggers differ from person to person, but headaches can be a symptom of heat-related disorders, such as heat exhaustion. Although heat itself does not cause headaches, its effects on the body can. A heat-induced headache or migraine can feel like dull pain on both sides of the head and may get worse with activity. It can happen for several reasons, including dehydration, excessive sun exposure, or physical exertion in the heat. This article explains how environmental conditions and lifestyle factors during hot weather can cause headaches, the symptoms of heat-induced headaches, and how you can treat a headache brought on by heat. Halfpoint / Getty Images How Hot Weather Causes Headaches There are a few heat-related factors in your body and environment that can bring on a headache. Dehydration Many people look forward to the warmer summer months because they can do more activities and sports outside. However, heat also has some downsides. Not drinking enough fluids when you’re outside in hot weather can leave you with a dehydration headache. When you are dehydrated, you have less fluid in your body tissues and brain. When this happens, your brain tissues shrink and pull away from the skull, causing nerve pain. Drinking fluids will help get the tissue fluids back to a normal level and is often enough to fix the headache, too. Sun Exposure In some cases, sun exposure can trigger a headache or migraine. Photophobia is when a person has abnormal discomfort and sensitivity to light. It is a neurological symptom that happens because of problems with 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 helps you see. For this reason, even a blind person can get a photophobia-induced headache. Barometric Pressure Barometric pressure is the air pressure level in the atmosphere. Summertime thunderstorms are a common cause of barometric pressure changes. Research has shown that even small decreases in atmospheric pressure can induce a migraine or headache. Hormonal Changes Hot flashes are common during perimenopause. They are caused by changes in estrogen levels. Estrogen works with a part of the brain involved in regulating body temperature. Low estrogen levels can increase the body's temperature and cause common menopause symptoms like hot flashes and night sweats. Physical Activity Headaches can be caused by physical activity when the weather is too hot, leading to heat exhaustion. Heat exhaustion is when the body gets too hot and cannot cool itself down. This happens more commonly during warm and hot summer months, especially when it’s also humid. Other symptoms of heat exhaustion include: Dehydration Dizziness Muscle cramps Nausea and vomiting Heatstroke (which can be life-threatening) Heat Exhaustion vs. Heatstroke: What’s the Difference? 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 along with confusion, slurred speech, weakness, or numbness, call 911. Heat Exhaustion Symptoms Symptoms of heat exhaustion include: Heavy sweatingCold, clammy skinTirednessWeaknessHeadacheFaintingDizzinessNausea 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 activity during hot weather. Once you feel a heat headache coming on, take measures to keep it from getting worse like: Finding a place to cool down and rest Drinking water for hydration Trying over-the-counter (OTC) pain medications (e.g., ibuprofen or acetaminophen) When to Seek Medical Attention If your symptoms do not improve after about an hour of rest and fluids, call your 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 When Should You Worry About a Headache? Coping With Excessive Heat Sweltering weather can be a challenge and you can’t always avoid being in extreme temperatures. If you can't beat the heat, here are a few ways you can stay safe: Keep a water bottle with you and drink plenty of fluidsCheck the forecast to prepare for hot weatherKeep headache medicine on handWear lightweight and loose-fitting clothesStay with family or friends while in high heat in case someone needs helpWear and reapply sunscreen regularlyBring a sun umbrellaSit in a pool or go swimming to cool offChange your schedule to avoid the heat (if possible) Summary Headaches can be a symptom of heat-related disorders, such as heat exhaustion. Although heat itself does not cause headaches, it can put you in situations that 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, finding a place to cool down and rest, as well as drinking water for hydration, can help keep it from getting worse. You can also take OTC pain medications to relieve your head pain. If these measures are not helping, you may need to call your provider for treatment. If you have extreme headache pain or other concerning symptoms call 911 or go to the ER right away. Frequently Asked Questions What are the stages of heat illness? Heat illnesses are ailments caused by hot and humid weather. People can get a heat-related illness from physical activity in hot weather, or even just by being out in hot weather for too long. Some of the most common types of heat illness include:Heat cramps (muscle spasms)Heat rash (painful and red skin irritation)Heat exhaustionHeatstroke (a life-threatening condition when the body reaches 106 F quickly) Can you throw up from heat exhaustion? Nausea and vomiting are two of the main symptoms of heat exhaustion. Other symptoms include:Heavy sweatingCold, clammy skinTirednessWeaknessHeadacheFaintingDizziness Does heat make anxiety symptoms worse? High heat and humidity can cause anxiety and even make anxiety symptoms worse. Cortisol, a stress hormone, increases during the summer months, leading to increased anxiety in some people. 8 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Centers for Disease Control and Prevention. Heat stress - heat related illness. National Headache Foundation. Light and headache disorders: understanding light triggers and photophobia. Okuma H, Okuma Y, Kitagawa Y. Examination of fluctuations in atmospheric pressure related to migraine. SpringerPlus. 2015;4:790. doi:10.1186/s40064-015-1592-4 Johns Hopkins Medicine. Introduction to menopause. Cleveland Clinic. Heat exhaustion. Johns Hopkins Medicine. Headache. Centers for Disease Control and Prevention. Warning signs and symptoms of heat related illness. Kanikowska D, Roszak M, Rutkowski R, et al. Seasonal differences in rhythmicity of salivary cortisol in healthy adults. Journal of Applied Physiology. 2019;126(3):764-770. doi:10.1152/japplphysiol.00972.2018 By Sarah Jividen, RN Sarah Jividen, RN, BSN, is a freelance healthcare journalist and content marketing writer at Health Writing Solutions, LLC. She has over a decade of direct patient care experience working as a registered nurse specializing in neurotrauma, stroke, and the emergency room. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit