An electrolyte panel is a medical test performed on a sample of biological fluid that measures levels of electrolytes. It is most commonly used on the blood
, but this test is also possible on urine and cerebrospinal fluid
. Electrolytes are ions such as sodium, potassium, calcium, magnesium, bicarbonates, and certain proteins. An electrolyte panel may target one or more ions. The classic blood electrolyte panel studies serum sodium, sodium ion concentration, serum potassium, potassium ion concentration, serum chloride for chlorine ions, and sometimes serum calcium, and serum magnesium or bicarbonate concentration.