How common is nausea in heat exhaustion?

Heat exhaustion develops when the body loses fluid and salt through sweating and cannot cool itself effectively. Reduced circulation and overheating can bring on nausea, headache, dizziness, weakness, muscle cramps, and clammy skin. A person may feel faint or have a fast heartbeat. Nausea can also have unrelated causes, so the surrounding heat exposure and other symptoms matter.

Move out of the heat as soon as symptoms begin. Heat exhaustion can progress to heatstroke, which is a medical emergency, especially if mental alertness changes or sweating stops despite very hot skin.

Stop exertion and rest in a cool, shaded or air-conditioned place. Loosen extra clothing and cool the skin with wet cloths or cool air. Sip water or an oral rehydration drink if you are awake and able to swallow. Do not return to strenuous activity until you feel fully recovered, and arrange medical advice if symptoms do not improve promptly.

Call emergency services for confusion, unusual behaviour, collapse, seizures, loss of consciousness, or very hot skin with worsening symptoms. Do not give drinks to someone who is confused or unable to swallow. Urgent assessment is also needed for ongoing vomiting, severe weakness, or symptoms that fail to settle after cooling and fluids.

Ask how to plan fluids during heat exposure, whether medicines or health conditions increase your risk, how soon to resume exercise, and which symptoms require emergency action.