What should you know about slight heat stroke?

Heat stroke occurs when the body cannot release heat effectively and temperature regulation starts to fail. Confusion, unusual behaviour, collapse, seizures, hot skin, severe weakness or loss of consciousness are particularly concerning. Sweating may be present or absent, so a person should not be reassured by damp or dry skin alone.

Heat exhaustion can cause heavy sweating, thirst, dizziness, headache and weakness without the same signs of altered mental state. It can progress to heat stroke, especially after exertion, in hot environments or when fluid loss is substantial.

Call emergency services and stay with the person. Move them into shade or air conditioning, remove excess clothing, and cool the skin with wet cloths, cool water or fans. Do not give drinks to someone who is confused, drowsy, vomiting or unable to swallow safely. Do not delay urgent care while trying to cool them. Medical teams may consider IV fluid therapy and monitoring.

Seek emergency help immediately for confusion, fainting, seizure, severe breathing difficulty, repeated vomiting, inability to drink, or a person who remains very hot and unwell after cooling. Someone with heat-exhaustion symptoms that do not improve promptly in a cool setting also needs urgent assessment. Fever-like symptoms can occur with heat illness, but heat stroke should not be treated as an ordinary fever.

Could this have been heat exhaustion or heat stroke? Does the person need observation or blood tests? How should work, exercise, medicines or hydration be adjusted before returning to heat?