The diagnosis of trichiniasis in man is usually not established until at least one to two weeks after infection, at a time when invasion of the muscles by the young larvae has already begun. In the treatment of the disease it would therefore seem desirable to employ an agent which would destroy either the young larvae circulating in the blood stream or those that had already reached the muscles and were still developing. From time to time, reports have appeared in the literature recommending such drugs as neoarsphenamine and antimony and potassium tartrate as being of value in the treatment of this stage of trichiniasis. In almost every instance, however, the reported treatment involved only a small number of cases, often only one, and was in no way sufficiently controlled. Since the mortality rate in trichiniasis is only about 6 per cent, nearly 95 per cent of patients recover without