Electrolytes are minerals in your blood and other body fluids that carry an electric charge.
Electrolytes affect how your body functions in many ways, including:
- The amount of water in your body
- The acidity of your blood (pH)
- Your muscle function
- Other important processes
You lose electrolytes when you sweat. You must replace them by drinking fluids that contain electrolytes. Water does not contain electrolytes.
Common electrolytes include:
Electrolytes can be acids, bases, or salts. They can be measured by different blood tests. Each electrolyte can be measured separately, such as:
- Ionized calcium
- Serum calcium
- Serum chloride
- Serum magnesium
- Serum phosphorus
- Serum potassium
- Serum sodium
Note: Serum is the part of blood that doesn't contain cells.
Sodium, potassium, chloride, and calcium levels can also be measured as part of a basic metabolic panel. A more complete test, called comprehensive metabolic panel, can test for these and several more chemicals.
The electrolytes - urine test measures electrolytes in urine. It tests the levels of calcium, chloride, potassium, sodium, and other electrolytes.
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