Bismuth Preparations. —Eagle106 has studied the toxicity and therapeutic efficacy in experimental syphilis in rabbits of three representative bismuth compunds—sodium and potassium bismuthotartrate ("bismosol"), serving as a prototype of the water-soluble bismuth compounds, a-carboxyethyl-b-methyl-bismuthononoate ("biliposol"), representative of fat-soluble compounds, and bismuth subsalicylate in oil, the preparation which has been most widely used in the treatment of syphilis. All these three preparations were given intramuscularly, a single injection being given approximately six weeks after intratesticular inoculation.
Bismuth Preparations. The results indicate that all three types of bismuth preparations studied are, mol for mol, from one half to two thirds as active therapeutically as is oxophenarsine hydrochloride similarly administered in a single injection in the treatment of experimental syphilis in rabbits. By virtue of their lower toxicity, two of the compounds, bismuth subsalicylate in oil and biliposol, provided margins of safety between the effective and toxic levels from six