Exertional heat stroke symptoms: what to know

This is a dangerous rise in body temperature caused by strenuous exercise, often in hot or humid surroundings. A person may become confused, unsteady, unusually agitated, drowsy or lose consciousness. The skin may feel hot and may be sweaty or dry; sweating can continue, so its presence does not rule out heat stroke. Headache, dizziness, nausea, vomiting, weakness, rapid breathing and a fast heartbeat can also occur. Heat exhaustion can worsen into heat stroke, but the two need different levels of response.

Stop the activity and call emergency services. Move the person to shade or a cool indoor area, remove excess clothing, and cool the body rapidly with cold wet cloths, a fan, or immersion in cool water when safe. Keep monitoring breathing and responsiveness. Do not give drinks to someone who is confused, vomiting repeatedly, having a seizure or unable to swallow. Do not leave the person alone or delay help while trying home remedies.

Treat suspected exertional heat stroke as an emergency, especially with confusion, collapse, seizure, severe weakness, or very hot skin after exercise. Emergency assessment is needed even if the person seems better after cooling, because internal injury can persist. Vomiting or a fever-like temperature after exertion also warrants prompt medical assessment; related information is available under Fever and Vomiting.

Ask what may have increased the risk, whether medicines or a medical condition affected heat tolerance, and how to return to exercise safely. You can also ask when oral fluids are appropriate and when IV Fluid Therapy may be considered.