How common is excessive thirst in heat exhaustion?

Heat exhaustion can develop when heat exposure and sweating outpace the body’s ability to cool itself and replace fluid. Thirst may come with heavy sweating, tiredness, nausea, muscle cramps, a fast pulse, or light-headedness. It can occur during outdoor work, exercise, travel, or time in a poorly cooled indoor space.

These symptoms need attention because heat illness can worsen. Thirst after being hot does not by itself confirm heat exhaustion; fever, infection, medicines, and other causes of dehydration can produce similar symptoms.

Stop activity, get to a cool shaded or air-conditioned place, loosen excess clothing, and rest. Take frequent small sips of cool fluid if you are awake and able to swallow. Cool the skin with a fan, damp cloths, or a cool shower. Do not return to strenuous heat exposure until symptoms have settled and you feel recovered.

Call emergency services if someone becomes confused, collapses, has a seizure, loses consciousness, or cannot drink. Seek urgent medical assessment when symptoms fail to improve with cooling and fluids, become worse, or occur in a person with a condition or medicine that affects fluid balance.

Ask whether the episode could have been heat exhaustion, whether any medicines increase heat sensitivity, and how to plan fluids, shade, breaks, and clothing for future hot days. Describe the setting, duration of exposure, activity, and symptoms that occurred.