When to worry about headache with heat exhaustion

Heat exhaustion follows loss of water and salt through sweating. Headache may occur with thirst, weakness, dizziness, nausea, muscle cramps, heavy sweating and cool, pale or clammy skin. It can worsen quickly when someone remains in heat, keeps exercising or cannot drink.

Stop activity and move to shade or an air-conditioned place. Loosen clothing, cool the skin with wet cloths or a fan, and take frequent small sips of water or an oral rehydration drink if fully awake and able to swallow. Stay with the person and reassess their alertness. Do not give drinks to someone who is confused, vomiting repeatedly or unable to swallow safely.

Call emergency services for confusion, unusual behaviour, loss of consciousness, seizure, inability to drink, repeated vomiting, severe breathing difficulty, or skin that is very hot with little or no sweating. Arrange urgent assessment when headache remains severe, symptoms worsen, or there is no clear improvement after cooling and fluids. People who are pregnant, older, very young, or living with serious illness may need earlier advice.

Ask how to replace fluids safely, whether your medicines increase heat sensitivity, how long to avoid strenuous activity, and what symptoms should trigger emergency help. Mention the heat exposure, amount you drank, sweating, vomiting, urine changes and any faintness.