How long does oral rehydration therapy take to work for heat exhaustion?

Heat exhaustion can follow prolonged heat exposure or heavy sweating and may cause weakness, headache, nausea, dizziness, clammy skin, and thirst. The solution replaces water and salts, while cooling helps the body lower its temperature. Improvement should include clearer thinking, less dizziness, easier drinking, and greater strength. Oral treatment cannot safely manage a person who is confused, collapsing, or unable to swallow.

Stop exertion and move the person into shade or an air-conditioned place. Remove unnecessary clothing, cool the skin with wet cloths or a fan, and let the person rest. If fully awake and able to swallow, offer frequent small sips of correctly mixed oral rehydration solution. Avoid returning to heat or exercise while symptoms remain. Stay with the person and watch for changes in alertness and breathing.

Call emergency services immediately for confusion, loss of consciousness, seizure, inability to drink, severe breathing difficulty, or a rapidly worsening condition. Do not force fluids into an unconscious or confused person. Arrange urgent medical assessment if there is no clear improvement with cooling and careful sipping over a short period, or if vomiting prevents hydration. Heat illness can worsen even after the person leaves the hot environment.

Ask whether the episode was heat exhaustion or a more serious heat illness, when normal activity is safe, and how to replace fluids during future hot-weather work or exercise. Mention medicines and medical conditions that may alter heat tolerance or fluid needs.