Physiological and Pharmacological Studies of Magnesium Salts

I n t r o d u c t o r y . T h e narcotic effect as well as the toxicity of magnesium salts, when introduced subcutaneously, depend to a great degree upon the readiness with which they are eliminated from the body. By what path are these salts eliminated? Are they excreted by the intestinal canal or are they eliminated through the kidneys? Meltzer and Auer" state that from their experiments they gained the impression " t h a t animals which urinated frequently had a better chance for recovery. Early urination seemed also to prevent the full development of anesthesia. Furthermore it seems that magnesium sulphate after subcutaneous injection acted as a diuretic." Such observations seemed to indicate that the kidneys are taking an essential share in the elimination of the magnesium salts. On the other hand J. B. MacCallum a states that magnesium salts (magnesium chloride) not only do not act as diuretics, but exert directly an inhibitory effect upon the urinary secretion. Furthermore from a remark recently made by Mendel it seems to follow that magnesium as an alkali earth leaves the body by the bowel. Mendel 4 states that the studies of the paths of excretion for inorganic compounds seem to " indicate a noteworthy difference in the mode of elimination of these alkali metals in contrast with corresponding salts of the alkali earths. The latter have been shown to leave the body in far greater quantity by the bowel than in the urine."