The inhibitory influence of magnesium upon some of the toxic effects of eserin

Abstract

In a paper on the relation of magnesium salts to gastrointestinal peristalsis, Meltzer and Auer 2 stated that they were able to completely inhibit the general muscular tremor caused by eserin, by means of injections of magnesium sulfate.

Matthews and Jackson 3 stated later they did not obtain a like result. At Dr. Meltzer's suggestion, an attempt was then made to establish the facts in the case and to determine any other points of interest in the antagonism between these two drugs.

My results and methods may be briefly reported as follows:

First; a method of registering the general fibrillary muscular contractions was worked out, the best result being obtained by stitching a tambour to the skin over the gluteal muscles, with the leg in a flexed position.

Second; while writing the fibrillary tremor caused by eserin, MgSO⁴ 1 was slowly injected into the jugular vein. The result was an invariable stoppage of all tremor. This stoppage was brought about in from one half to one and a half minutes according to the rapidity of injection of magnesium. If the initial dose of MgSO⁴, was sufficient, there was no recurrence of eserin tremor.

Third; an attempt was made to ascertain whether MgSO₄, could be used as an antidote for eserin poisoning. Eserin was injected into rabbits intramuscularly in quantities usually sufficient to kill. Afterwards, MgSO₄, was injected into the ear vein until the effect of eserin disappeared. In twenty two trials, the animals survived strongly toxic, and fatal, doses. The general tremor and convulsive movements stopped after the injection of from 2 to 4 C.C. of MgSO₄, solution. The magnesium effect was usually marked, however. If the depression of respiration was sufficient to cause danger of asphyxia, the injection of I C.C. of CaCl, solution into the ear vein was usually sufficient to counteract the action of MgSO₄, on the respiration.