It's usually apparent to doctors if you have heatstroke, but laboratory tests can confirm the diagnosis, rule out other causes for your symptoms and assess organ damage. These tests include:
- Rectal temperature to check your core body temperature. A rectal temperature is the most accurate way of determining your core body temperature and is more accurate than mouth or forehead temperatures.
- A blood test to check blood sodium or potassium and the content of gases in your blood to see if there's been damage to your central nervous system.
- A urine test to check the color of your urine, because it's usually darker if you have a heat-related condition, and to check your kidney function, which can be affected by heatstroke.
- Muscle function tests to check for serious damage to your muscle tissue (rhabdomyolysis).
- X-rays and other imaging tests to check for damage to your internal organs.