The only way to know for sure if your potassium level is healthy is to have a blood test. The test measures how much potassium is in your blood.

The blood test is like many other blood tests that you may be familiar with. A small needle is placed into a vein on your arm and your blood is drawn out into a tube. The blood is sent to lab to be tested.

Potassium may be called something else in your test results. If you do not see ‘potassium’, look for either:

  • Serum potassium
  • K

A potassium of higher than 5.2 millimoles per liter (mmol/L) is usually considered high but your doctor or lab might use slightly different numbers. Talk to your doctor about what your test results mean.

Because very high potassium (higher than 6.0 mmol/L) can be dangerous, your doctor or nurse may contact you first if your results are unusually high. In this case, they may ask you to go to an emergency room or hospital.