Heat illnesses are generally diagnosed based on their symptoms.
With heat exhaustion, a healthcare professional will start by checking your temperature. You will be asked what you were doing before coming into the emergency room and what symptoms you are experiencing.
Because heatstroke is a dangerous condition, people who experience it should call 911 or be brought to an emergency room. At the emergency department, your temperature will be taken.
You will also have tests done to check organ function, blood tests, urine tests, and other testing the healthcare provider thinks might be helpful.
If it is determined you do not have heatstroke, they will look for other causes of symptoms. If it is heatstroke, you might be admitted to the hospital for treatment or you will receive treatment in the emergency room.