Apr. 15, 1921 
Carbon Tetrachlorid for the Removal of Worms 
165 
this tapeworm, so the drug must be regarded as of no value against 
Dipylidium, and this will probably be true of tapeworms of other genera. 
As regards the findings in the case of nematodes, they may be summa¬ 
rized as follows: 
Carbon tetrachlorid, administered in capsules in dose rate of 0.1 m. 
p. k. to 4 dogs, removed 23 hookworms and left 30, an efficacy of 43 per 
cent; it removed 34 ascarids and left 9, an efficacy of 79 per cent; it 
removed no whipworms and left 2, an efficacy of o per cent. 
Carbon tetrachlorid, administered in capsules in dose rate of 0.2 m. p. 
k. to 4 dogs, removed 1 hookworm and left 3, an efficacy of 25 per cent; 
it removed 1 ascarid and left 1, an efficacy of 50 per cent; it removed no 
whipworms and left 11, an efficacy of o per cent. 
Carbon tetrachlorid, administered in capsules in dose rate of 0.3 m. p. k. 
to 9 dogs, removed 34 hookworms and left none, an efficacy of 100 per 
cent; it removed 6 ascarids and left none, an efficacy of 100 per cent; it 
removed 19 whipworms and left 210 plus scores uncounted in one animal, 
an efficacy of less than 16 per cent. 
Carbon tetrachlorid, administered in capsules in dose rate of 1 m. p. k. 
to 1 dog, removed 2 ascarids and left 1, an efficacy of 67 per cent; it re¬ 
moved 16 whipworms and left none, an efficacy of 100 per cent; no 
hookworms were present in this dog. 
Carbon tetrachlorid, administered in capsules in dose rate of 1.5 m. 
p. k. to 1 dog, removed no worms and none were found post mortem; no 
conclusions as to efficacy. The intent in this experiment was to ascer¬ 
tain whether any bad results would follow the administration of such a 
large dose. No bad effects of the treatment were observed ante mortem 
or post mortem. , 
It appears from the foregoing experiments that a dose rate of 0.3 
m. p. k. is necessary to secure a dependable efficacy of carbon tetra¬ 
chlorid against hookworms and ascarids. Whipworms, as the writer has 
pointed out in a number of papers, can not be removed with any cer¬ 
tainty by single-dose treatment with any anthelmintic of which he is 
aware. 
In the following experiments carbon tetrachlorid was administered by 
drench instead of in capsules to fasting dogs, without purgation. 
Dog 409; 0.3 m. p. k.; 1 hookworm first day; p. m., 1 hookworm, 25 
whipworms; 50 per cent vs. hookworms, o per cent vs. whipworms. 
Dog 411; 0.3 m. p. k.; 8 hookworms and 25 ascarids first day, 2 asca¬ 
rids third day; p. m., 16 whipworms; 100 per cent vs. hookworms and 
ascarids, o per cent vs. whipworms. 
Dog 412; 0.3 m. p. k.; 7 hookworms and 16 ascarids first day; p. m., 
21 hookworms, 22 ascarids, 54 whipworms; 25 per cent vs. hookworms, 
40 per cent vs. ascarids, o per cent vs whipworms. 
In the experiment described above carbon tetrachlorid, administered 
without capsules at a dose rate of 0.3 m. p. k. to 3 dogs, removed 16 
