Headache after being in the sun: what to know

A headache after being in the sun may result from heat, fluid loss, glare, fatigue, or a migraine trigger. It can occur after time outdoors even without visible sunburn. Pay attention to thirst, sweating, dizziness, nausea, cramps, weakness, sensitivity to light and changes in alertness, as these clues help distinguish a mild headache from heat-related illness.

Heat and sweating can reduce body fluid and salt, while bright glare may provoke headache or migraine. Heat Exhaustion may include heavy sweating, weakness, dizziness, nausea and cool, clammy skin. Dehydration can cause thirst, dry mouth, dark urine and light-headedness. A headache with fever, cough or sore throat may have an infectious cause such as COVID-19 or a Common Cold. Allergic Rhinitis can also be aggravated outdoors and cause nasal symptoms.

Leave the sun, loosen extra clothing and rest in a cool, shaded or air-conditioned place. Sip water or an oral rehydration drink, and use cool wet cloths on the skin. Avoid strenuous activity until you feel fully recovered. Sunglasses and a hat can reduce glare on future outings, and regular breaks help in hot weather. If you take regular medicines or have a condition affecting fluid balance, ask a pharmacist or clinician how to rehydrate safely.

Call for urgent medical help if there is confusion, collapse, fainting, seizure, inability to drink, repeated vomiting, worsening weakness, very hot skin, or symptoms that do not improve after cooling. Seek urgent assessment for a sudden severe headache, new weakness or numbness, stiff neck with fever, or a new vision problem. Arrange a medical review when sun-related headaches recur or interfere with normal activity.

Could heat, dehydration or migraine explain my episodes? How much fluid is suitable for me? Which medicines affect heat tolerance or fluid balance? What is my personal plan for future outdoor activity?