TREATMENT OF TRYPANOSOMIASIS. 31 



Schilling and Jaffe also have shown the unquestionable value of arsenophenyl- 

 glycin in the treatment and cure of mice and rats infected with the nagana 

 trypanosoma, the animals frequently being cured by a single injection of the 

 drug. In their experiments with horses, all of the animals died, apparently 

 from the effect of the drug in the dosest employed. 



Mesnil and Kerandel inoculated three monkeys infected with Trypanosoma 

 gabiense with arsenophenylglycin. In two, the parasites disappeared and had not 

 returned after about three and one-half months. In the third a relapse occurred , 

 then the second injection was given and for the following two and one-half 

 months the animal was free from parasites. They also demonstrated the 

 prophylactic value of the drug in several monkeys and have obtained good 

 results with it in the treatment of four guinea pigs infected with the trypanosoma 

 of Togo. 



Eckard has treated 19 eases of sleeping sickness with arsenophenylglycin. 

 Twenty-four hours after the injection, the parasites could no longer be found 

 .in the patients' blood. The author was unable to state definitely the value 

 of the drug, owing to the short time which had elapsed between the time the 

 injections were made and the date of the report. 



Breinl and Nierenstein report experiments with 20 rats, each of which 

 received the dose of arsenophenylglycin recommended by Roehl, 0.4 gram per 

 kilo or a smaller dose. All died from the effect of the drug. Of 5 guinea pigs 

 infected with trypanosomata and treated, 3 died ; 2 from the effects of the drug, 

 and 2 were alive and well after 240 days. Three monkeys were treated with a 

 single dose. Two were alive and well 270 days later. One died from the effects 

 of the drug. Dogs could also be cured of infection by repeated injections, even 

 in advanced cases. Four donkeys and 1 pony were treated with subcutaneous 

 inoculations of the drug. One donkey died after a dose of 0.1 gram per kilo. 

 Another succumbed apparently to the local gangrene caused by the drug. In 

 the other three, large injections did not save the animals which died later of 

 infection. These authors believe that the drug is superior to atoxyl, but that the 

 chance of successful treatment with it diminishes as the size of the animal 

 increases. 



Zupitza has employed arsenophenylglycin in 25 cases of sleeping sickness. 

 The treatment appears to be the most favorable which had been attempted at 

 the time the report was made. The parasites disappeared from the blood more 

 quickly after the injection of arsenophenylglycin than after any other drug 

 employed. Relapses had occurred in some of the cases. The time of observa- 

 tion had been too short to draw any more definite conclusions. Twelve horses 

 and 7 donkeys were also treated with this drug. The statement was made that 

 one-half of them had been at work for 5 months after the discovery and treat- 

 ment of the infection. At present Zupitza's article is not at hand and we have 

 only been able to consult a review. We can not therefore conclude whether these 

 animals were free from trypanosomata and had been cured. 



EXPERIMENTS WITH ARSENOPHENYLGLYCIN" IN MONKEYS. 



Dosage. — One of the first questions which seemed necessary to answer 

 was the dosage of arsenophenylglycin most favorable for the treatment 

 of these animals. Ehrlich had suggested to us about 0.1 gram per kilo 

 of body weight. However, when this amount was injected into normal 

 monkeys, it was found to kill far too high a percentage of the animals 

 for the dose to be practical for treatment. Hence we found it necessary 

 to employ the drug in smaller quantities. 



