Oct. 1, 1924 
Critical Tests of Miscellaneous Anthelmintics 
315 
DISCUSSION 
It has been shown experimentally by 
Hall and Foster ( 18 ) 2 and by Hall in a 
number of subsequent papers that 
chenopodium at the rate of 0.1 cc. per 
kilogram of weight of animal is a quite 
dependable anthelmintic for removing 
ascarids from dogs and that when given 
with an ounce of castor oil it removes 
all ascarids present in almost all cases. 
Chenopodium is also fairly effective in 
removing hookworms from dogs. It 
has also been shown by Hall (18) and 
subsequently by Hall and Shillinger 
( 24 ) that carbon tetrachloride at the 
rate of 0.3 cc. per kilogram of weight 
of animal is a quite dependable anthel¬ 
mintic for removing hookworms from 
dogs, and this has been confirmed in ex¬ 
tensive use in veterinary practice for 
the past 2 or 3 years. The work of 
Allen (2) and of Hanson and Van Vol- 
kenburg (26) shows that the same is 
true for hookworms in foxes. Carbon 
tetrachloride is also fairly effective in 
in removing ascarids. It has also been 
shown by Hall and Shillinger (23) that 
arecoline hydrobromide, first proposed 
as a taeniacide for dogs by Lentz (82 ), 
removes all tapeworms present in the 
majority of cases, though it fails to re¬ 
move some or all in a rather large mi¬ 
nority of cases, a thing not uncommon 
with tapeworm remedies. Theoreti¬ 
cally, a combination of carbon tetra¬ 
chloride, chenopodium, and arecoline 
hydrobromide should make a good an¬ 
thelmintic for removing the ascarids, 
hookworms, and tapeworms from dogs 
and might prove a useful “shotgun” 
prescription under conditions prevent¬ 
ing fecal examination to determine the 
sort of worms present. Hall (18) found 
the combination of carbon tetrachloride 
and chenopodium at a dose rate of 0.3 
cc. per kilogram of weight of animal, as 
given here, entirely effective in remov¬ 
ing hookworms and ascarids from dogs. 
The arecoline hydrobromide should pro¬ 
vide the necessary purgation for the 
chenopodium and carbon tetrachloride. 
The fact that the combination re¬ 
moved all the ascarids from 2 of 3 in¬ 
fested dogs, giving what may be termed 
cures in 67 per cent of cases; failed en¬ 
tirely in one case, or 33 per cent of the 
cases; and removed 90 per cent of the 
total of 10 worms present, indicates 
that there is little loss of efficacy of che¬ 
nopodium and carbon tetrachloride 
against ascarids when given with areco¬ 
line hydrobromide. That a single asca- 
rid might be missed occasionally is more 
or less to be expected. 
It removed all the hookworms from 
7 of 9 infested dogs, giving cures in 
78 per cent of the cases; removed 83 
per cent of the worms in one case and 
7 per cent in another, giving partial 
cures in 22 per cent of the cases; and 
removed 46 per cent of the total of 
48 worms present. These facts indi¬ 
cate that carbon tetrachloride and 
chenopodium, when given with are¬ 
coline hydrobromide, show a distinct 
loss of efficacy and dependability 
against hookworms. 
It removed all the whipworms from 
1 of 11 infested dogs, giving cures in 
9 per cent of the cases; removed no 
worms in 6 cases, or 55 per cent of the 
cases; removed 87,75, 50, and 48 per cent 
of the worms in 4 cases, giving partial 
cures in 36 per cent of the cases; and 
removed 57 per cent of the total of 
476 worms present. This is not a bad 
showing, and is perhaps better than 
that of the individual drugs used in 
the combination, although this is not 
easy to ascertain owing to the erratic 
action of drugs against whipworms. 
Whipworms are not good subjects 
for ordinary anthelmintic tests, as the 
efficacy of a drug appears to depend 
on the accident of the entry of the 
drug into the cecum, rather than on 
the effect of the drug on the worms 
with which it comes in contact. 
It removed none of the 70 tape¬ 
worms present in two cases, giving 
complete failures with these worms. 
The striking thing about the experi¬ 
ments is this total failure of the 
arecoline hydrobromide against tape¬ 
worms. The authors have shown in a 
previous paper (28) that all the tape¬ 
worms were removed from 4 of 7 
animals treated and none from 3 
animals, so it is evident that depend¬ 
able action can not be expected in 
nearly all cases. Unfortunately, the 
series of available animals included 
too few with tapeworms to make this 
a good test, but it certainly gives little 
reason for expecting much in the way 
of tapeworm removal from this com¬ 
bination. 
In general, this combination does 
not give in test the results that would 
be expected from a theoretical con¬ 
sideration. It would probably main¬ 
tain a rather high efficacy against 
ascarids, show a decided decrease of 
efficacy against hookworms and tape¬ 
worms, and at least average efficacy 
against whipworms, as compared with 
its constituents, but could hardly be 
recommended as a useful combination 
for cases where fecal examinations 
2 Reference is made by number (italic) to “ Literature cited,” pp. 331-332. 
