ACUTE INTOXICATION CATS. 53 



for the delayed death of some animals many days after a single dose of caff ein was given. 

 Among the factors which undoubtedly influence toxicity, season should be considered, 

 while the presence of a diseased condition undoubtedly tends to decrease the resist- 

 ance of the guinea pig to caffein. Diet was without any influence on the toxicity of 

 the single dose of caffein. 



EXPERIMENTS ON CATS. 



These experiments were performed on well-fed animals which were kept under 

 observation for several days before the tests with caffein were made. The diet con- 

 sisted of meat exclusively. In some cases the urine was examined for albumin and 

 sugar before caffein was given. No tests with caffein were made if large amounts of 

 albumin were found. It may be remarked that sugar was never found in cats before 

 the administration of caffein, but that considerable amounts of it were found in some 

 cases after it was given. Studies by various modes of administration were made, by 

 subcutaneous injection, intraperitoneally, or by mouth. Attention was also directed 

 to the resistance to caffein in young cats, several experiments on kittens being made 

 with this object in view. 



SUBCUTANEOUS INJECTION. 



Host stated that caffein is eliminated in the urine unchanged after its introduction 

 into the body and that the amounts found varied with different species of animals. 

 In the rabbit the amount eliminated was about 21 per qent; in the dog about 8 per cent ; 

 and in the cat somewhat less than 2.5 per cent. It would appear, therefore, that the 

 cat decomposes caffein more readily than the rabbit or dog; its resistance consequently 

 ought to be greater than that of the other animals. Moderately large doses were accord- 

 ingly employed in the preliminary experiments (series A), but the results obtained, as 

 shown in the protocols, indicated that caffein is fully as toxic for the cat as for the 

 rabbit or dog. The doses were then decreased and experiments were performed in 

 order to ascertain the smallest toxic as well as the smallest fatal dose. 



SERIES A 



Three decigrams of caffein per kilo were administered in these experiments. The 

 results are shown in the following protocols: 



Cat 4. Black and white. Weight, 1,440 grams. 



May 26: 10.05 a. m., 22 cc 2 per cent caffein (0.3 gram per kilo) injected subcuta- 

 neously; 11.10 a. m., copious salivation, cat irritable, muscular stiffness present, but 

 no tetanus; 11.45 a. m., cat restless, convulsions, attacks of short duration, no paralysis 

 observed after the convulsions, pupils dilated; 4.45 p. m., cat quiet, slight paralysis 

 present. 



May 27: Cat exhausted. 



May 28: Found dead. 

 Cat 5. Black and white male. Weight, 1,396 grams. 



June 3: 10 a. m., 21 cc of 2 per cent caffein (0.3 gram per kilo) injected subcuta- 

 neously; 12 noon, found dead. 



Although there was considerable difference in the duration of life following the 

 injection of the same dose of caffein per kilo, the final outcome was the same, as both 

 cats died from the effects of the drug. One died within 2 hours and the other lived 

 more than 30 hours after its administration. Three decigrams of caffein per kilo is, 

 therefore, surely fatal to these animals. Tests made with smaller doses are shown in 

 the following experiments: 



SERIES B. 



In these experiments the doses employed ranged between 0.20 and 0.25 gram caffein 

 per kilo. 



