High or low electrolyte levels can be caused by several conditions and diseases. Generally, it is affected by how much electrolyte is consumed through diet and absorbed by the body, the amount of water in a person's body, and the amount eliminated by the kidneys. Electrolyte levels are also affected by some hormones such as aldosterone. It is a hormone that conserves sodium and promotes the elimination of potassium, and natriuretic peptides, which increase the elimination of sodium through the kidneys.
With respect to the amount of water in a person's body, for example, if a person's kidneys are not functioning properly, it may retain excess fluid. This results in a dilution effect on sodium and chloride so that they fall below normal concentrations. On the other hand, people who experience severe fluid loss may show an increase in the level of potassium, sodium, and chloride concentrations. Some conditions such as heart disease and diabetes might also affect the fluid and electrolytes balance in the body, thus causing abnormal levels of electrolytes.
The test will detect the underlying cause which will help with future treatment (if required) to restore proper electrolyte balance. If left untreated, an electrolyte imbalance can lead to various problems, including dizziness, cramps, irregular heartbeat, and possibly death (in rare cases).
There is no precaution required before going in for the test.
Treatment for an electrolyte imbalance will depend on which electrolyte is out of balance and by how much. For example, if you have a sodium imbalance you may be advised to lower your salt intake (if sodium is too high) or reduce your fluid intake (if sodium is too low).