Electrolytes (Monograph)
Drug class: Replacement Preparations
VA class: TN400
CAS number: 71-50-1
Introduction
Electrolyte solutions provide electrolyte supplementation and water for hydration.
Uses for Electrolytes
For further information on chemistry and stability, pharmacology, uses, cautions, and dosage and administration of electrolyte solutions, specialized references on fluids and electrolytes and the manufacturers’ labeling should be consulted.
Pharmacology
Multiple electrolyte solutions are used as sources of electrolytes and water for hydration, or as alkalinizing agents. Multiple electrolyte solutions containing a carbohydrate source are used as sources of calories.
Multiple electrolyte solutions provide electrolyte supplementation and water for hydration. Multiple electrolyte solutions containing a carbohydrate source (e.g., dextrose, fructose, invert sugar, alcohol) also provide calories; solutions containing bicarbonate precursors (e.g., acetate, citrate, lactate) serve as alkalinizing agents. Multiple electrolyte solutions are capable of inducing diuresis depending on the clinical condition of the individual.
Sodium is the major cation of extracellular fluid and functions principally in the control of water distribution, fluid and electrolyte balance, and osmotic pressure of body fluids. Sodium is also associated with chloride and bicarbonate in the regulation of acid-base balance. Chloride, the major extracellular anion, closely follows the physiologic disposition of sodium, and changes in the acid-base balance of the body are reflected by changes in serum chloride concentration.
Potassium is the major cation of intracellular fluid and is essential for maintenance of acid-base balance, isotonicity, and electrodynamic characteristics of the cell. Potassium is an important activator in many enzymatic reactions and is essential to a number of physiologic processes including transmission of nerve impulses; contraction of cardiac, smooth, and skeletal muscles; gastric secretion; renal function; tissue synthesis; and carbohydrate metabolism. For additional information on potassium, see Potassium Supplements 40:12.
Calcium, an important cation, is essential for maintenance of the functional integrity of nervous, muscular, and skeletal systems and cell membrane and capillary permeability. Calcium is an important activator in many enzymatic reactions and is essential to a number of physiologic processes including transmission of nerve impulses; contraction of cardiac, smooth, and skeletal muscles; renal function; respiration; and blood coagulation. Calcium also plays regulatory roles in the release and storage of neurotransmitters and hormones, in the uptake and binding of amino acids, and in cyanocobalamin (vitamin B12) absorption and gastrin secretion.
Magnesium, a principal intracellular cation of soft tissue, is mainly involved as a cofactor in enzymatic reactions associated with the metabolism of carbohydrates and protein. Magnesium is also involved in neurochemical transmission and neuromuscular excitability.
Phosphate is a major intracellular anion that participates in providing energy for metabolism of substrates and contributes to important metabolic and enzymatic reactions in almost all organs and tissues. Phosphate exerts a modifying influence on calcium concentrations, a buffering effect on acid-base equilibrium, and has a major role in the renal excretion of hydrogen ions. The ammonium ion (NH4 +), plays a major role in the maintenance of the acid-base balance of the body. The major site of ammonia metabolism is in the liver, where ammonia is converted to urea. Ammonia also participates in the synthesis of glutamine. Ammonium chloride is added to electrolyte solutions for its acidifying effect.
Gluconate, acetate, lactate, and citrate are organic ions that are hydrogen ion acceptors and contribute bicarbonate during their metabolism.
AHFS DI Essentials™. © Copyright 2025, Selected Revisions January 1, 2002. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.