In a recent article1 dealing with 3-acetyl-amino-4-hydroxyphenyl-1-arsonic acid, generally known as acetarsone or stovarsol, we expressed the view that the problem of the toxicity of this compound requires reconsideration, since we found lower values for the toxicity of acetarsone than those heretofore obtained by other workers in this field.
Soon after the discovery of the antisyphilitic action of this preparation, conflicting reports regarding its toxicity appeared in the literature. When, in 1922, Levaditi, Navarro-Martin and Fournier2 first recommended acetarsone (stovarsol) for use in the treatment for syphilis, they stated that the lethal dose of the drug, when given to the rabbit by mouth, is 0.6 Gm. per kilogram of body weight, but that a dose of from 0.3 to 0.4 Gm. is easily tolerated by the animals, some rabbits having tolerated well even 0.7 Gm. of stovarsol per kilogram. When, however, the toxicity of the