Heat exhaustion symptoms, first aid and treatment

Heat exhaustion occurs when heat exposure or exertion causes more fluid and salt loss than the body can replace. The person may be pale, clammy, weak, thirsty or unsteady, and may develop nausea, cramps or headache. It can worsen if activity continues. [Dehydration](/conditions/dehydration/) may accompany it, but symptoms can have other causes, so failure to improve after cooling should be taken seriously.

Move the person to shade or air conditioning and stop all activity. Help them lie down, loosen clothing and cool the skin with wet cloths, a fan or cool packs wrapped in fabric. If they are awake and swallowing normally, offer small sips of water or an oral rehydration drink. Do not force fluids or give anything by mouth to someone confused, vomiting repeatedly or not fully alert. Avoid alcohol and return to heat. [Excessive Sweating](/symptoms/excessive-sweating/) and [Excessive Thirst](/symptoms/excessive-thirst/) can help track ongoing loss.

Call emergency services for confusion, fainting, seizure, severe breathing difficulty, inability to drink, repeated vomiting or worsening despite cooling. A person who is difficult to wake needs immediate assessment. Seek medical advice if weakness, [Dizziness](/symptoms/dizziness/), [Headache](/symptoms/headache/) or [Dark Urine](/symptoms/dark-urine/) persists.

Ask when normal activity is safe, which fluids suit you, how to prevent recurrence, and whether medicines or health conditions make heat exposure more hazardous.