The components of living cells and body fluids which are present as electrically charged ions. They can be divided into the positively charged Cations Potassium, Sodium, Magnesium and Calcium and the negatively charged Anions Chloride, Phosphate and Bicarbonate. Electrolytes are responsible for maintaining correct fluid balance between the intracellular and extracellular compartments of the body and for regulating the flow of nutrients into and waste products out of cells and from the body.
Electrolytes, particularly salt, may be supplemented in the diet when losses are expected to be higher than intake, for example when sweat loss is raised through exercise in hot conditions. Sterile balanced electrolyte solutions may be given intravenously (saline drips) to dehydrated or ill horses.