Glycerophosphates

GLYCEROPHOSPHATES, salts of glycerophosphoric acid, are neutral, soluble in water, and insoluble in alcohol; they often possess an alkaline reaction. With common reagents for phosphoric acid, glycerophosphates do not produce a precipitate (in the cold); with lead acetate, they form a precipitate that is difficult to dissolve in acetic acid, but easily soluble in nitric acid. Since glycerophosphoric acid is very common in nature, being a component of lecithins, and is present in blood, meat, brain, nervous and other tissues, this circumstance gave French scientists—Pasqualis, and later Robin—the reason, starting in 1894, to use glycerophosphates for various diseases of the nervous system as agents improving general nutrition, and especially the nutrition of the nervous system. However, the assumption about the particularly favorable effect of glycerophosphate on the body is currently considered unjustified, especially since it has already been proven that glycerophosphates, when introduced into the body, decompose into phosphates, which are excreted from the body in the form of inorganic salts, while the glycerin undergoes oxidation and is normally involved in metabolism; the body builds the necessary organic phosphorus compounds itself from inorganic ones. In medical practice, salts of calcium, iron, and sodium are mainly used as tonico-nervina (nerve tonics). The main salts are: Natrium glycerophosphoricum, C₃H₅(OH)₂.O.PO.(ONa)₂+3H₂O, a white crystalline powder, hygroscopic, easily soluble in water; the solution has an alkaline reaction. It is used subcutaneously in doses of 0.3–0.5 in a sterilized solution; internally, 1.0–2.0 per dose and up to 5.0–10.0 per day. Calcium glycerophosphoricum, C₃H₆(OH)₂.O.PO.(O₂Ca) + 2H₂O (or H₂O), a white powder, soluble in 40 parts of water; when a solution saturated in the cold is heated, a precipitate forms, which dissolves again upon cooling; the aqueous solution has an alkaline reaction. It is used internally at 0.2–0.5 three to four times a day or subcutaneously at 0.1–0.2 per dose. Ferrum glycerophosphoricum [C₃H₆(OH)₂.O.PO.O₂]₃Fe₂, a ferric salt, representing greenish-yellow flakes, slowly soluble in water (at t°+20° up to 10%); the solution has a weakly acidic reaction; it contains 14–15% iron. It is used for anemia, chlorosis, general weakness, and as a tonicum for the intestines in mixtures, powders, and pills at 0.1–0.2 per dose; for adults, it is also administered subcutaneously at 0.1. The indicated preparations and similar ones are quite often used for neurasthenia with phosphaturia, for depression of the nervous system, chlorosis, tuberculosis during the recovery period after severe illnesses, etc. In addition to the salts mentioned above, the following complex preparations have been proposed: tablets used for sclerosis; they contain per dose 0.5 sodium chloride, 0.05 sodium sulfate, 0.02 magnesium phosphate, 0.02 sodium carbonate, 0.02 sodium phosphate, and 0.05 calcium glycerophosphate. Elixir glycerophosphat. consists of 25.0 sodium glycerophosphate, 8.75 calcium glycerophosphate, 8.0 phosphoric acid (85%), 300 cubic cm of glycerin, a small amount of aromatic elixir, and water up to a liter. A. Ginaberg.