What is being tested?Potassium is present in all body fluids, but most potassium is within your cells, with only a very small amount in the serum or
plasma component of the blood. If potassium goes too low or too high, your health may be impaired. An abnormal concentration can alter the function of the nerves and muscles; for example, in extreme cases you may experience heart rhythm disturbances or the heart muscle may even lose its ability to contract.
