58 



THE TOXICITY OF CAFFEIN. 



Cat 82. Gray female. March 3, weight 2, 450 grams; June 6, weight 2,750 grams. Diet, 

 150 grams of meat daily. 



June 7 : Given 0.4125 gram of caffein in 150 grams of meat, did not eat. 



June 8: Given 0.4125 gram of caffein in 150 grams of meat, refused to eat. 



June 9: Given 150 grams of meat without caffein, ate all of it. 



June 10: No food given. 



June 11: No food given. 



June 12: Given 0.4125 gram caffein in 150 grams of meat (150 mg per kilo), ate all 

 of it. 



June 13: Found dead. Autopsy: Lungs congested, liver congested; other organs 

 apparently normal. 

 Cat 100. Gray female. Weight, 2,740 grams. Diet, meat. 



July 17 : 3 p. m. , 17 cc of 2 per cent caffein (124 mg per kilo) given by mouth through 

 stomach tube at 3.20 p. m. ; 5 p. m., very irritable, but no other symptoms. 



July 18: Under observation all day, no symptoms. 

 Cat 93. Black and white female. Weight, 1,640 grams. 



July 17: 3.30 p. m., 10 cc (0.125 gram per kilo) of 2 per cent caffein given by mouth 

 through stomach tube. 



July 18: Under observation all day, no symptoms. 



From the results of the experiments of this series it appears that 0.15 gram caffein 

 per kilo may be fatal within a few hours after its administration, even if the drug is 

 mixed with a moderate amount of meat. Experiments 87 and 92 show, however, that 

 this amount may be borne by some individuals without any serious consequences, as 

 the cats were under observation for some time after they received caffein, and no 

 untoward symptoms were noticed in either of them during this time. It may be 

 remarked that cat No. 92 vomited shortly after it received caffein. It is practically 

 certain, therefore, that this amount of caffein in proportion to the weight of the animal 

 will in the great majority of cases prove fatal, and perhaps in a smaller percentage of 

 individuals it is surely toxic if it does not escape absorption. Smaller doses may 

 cause irritability in some individuals, but symptoms referable to nervous symptoms 

 of muscles were absent, as in experiments Nos. 93 and 100. The minimum fatal dose 

 of caffein for the cat when giveo by mouth is, therefore, 0.15 gram per kilo. 



TABLE 9. Subcutaneous injection; cats. 

 SERIES A. 



SERIES B. 



SERIES C. 



