322 
Journal o f Agricultural Research 
Vol. XXIX. No. 7 
post-mortem lesions due to the drug 
consisted in pronounced vascular in¬ 
jection of the abdominal blood vessels. 
Dog 648 was killed by the intraperito- 
neal injection of 20 cc. of a saturated 
solution of magnesium sulphate; the 
animal lay down, became unconscious, 
and died in about 15 minutes. The 
lesions due to the injection were similar 
to those in the case of dog No. 636. 
This method of killing dogs has been 
recommended, but no previous report of 
the post-mortem lesions has been 
noted. 
DISCUSSION 
Macht and Finesilver ( 34 ) have 
pointed out that the simultaneous ad¬ 
ministration of magnesium sulphate 
with other drugs diminishes or prevents 
the absorption of the other drugs, ap¬ 
parently by virtue of the well-known 
salt action which causes a flow of fluid 
from the walls of the digestive tract to 
the lumen and thus inhibits an absorp¬ 
tion current in the opposite direction. 
It follows from their conclusions that 
magnesium sulphate should not be 
given with other drugs where absorp¬ 
tion of these drugs with consequent 
systemic effects is desired. However, it 
would also appear that in the case of 
anthelmintics, and possibly of intestinal 
antiseptics, the simultaneous adminis¬ 
tration of magnesium sulphate would be 
valuable, all other things being equal, 
since such substances are commonly 
more or less toxic, their systemic effects 
are not desired, and it is advisable to 
limit their action to that on the fauna 
and flora of the digestive tract if possi¬ 
ble, leaving the host relative^ unaf¬ 
fected. The present experiments show 
that magnesium sulphate saved the 
lives of two dogs given 0.6 cc. per kilo¬ 
gram of chenopodium, a little more than 
the minimum lethal dose of 0.5 cc. per 
kilogram, and of one dog given double 
the minimum lethal dose, but failed to 
save one dog given 0.6 cc. per kilogram. 
The question arises whether the 
simultaneous administration of salts 
with anthelmintics will lessen the effi¬ 
cacy of the anthelmintic. The experi¬ 
ments reported above show that in 
therapeutic doses chenopodium with 
magnesium sulphate removed 15 out of 
16 ascarids from two infested dogs, all 
the hookworms ( 1 ) from another, and 
failed to remove tapeworms and whip¬ 
worms as might be expected. This 
drug therefore maintains its anthelmin¬ 
tic efficacy when given simultaneously 
with magnesium sulphate. Hall and 
Shillinger ( 25 ) have reported tests of 
the effect of magnesium sulphate ad¬ 
ministered simultaneously with carbon 
tetrachloride, and find the latter as 
effective against hookworms when ad¬ 
ministered in this manner as when ad¬ 
ministered without the salts. They 
were unable to obtain definite results as 
to the diminished toxicity of carbon 
tetrachloride given with the salts, as 
dogs tolerated very large doses of car¬ 
bon tetrachloride when given alone or 
with the salts. In human practice 
Lambert ( 28 ) finds that carbon 
tetrachloride is as effective when given 
with the salts as when given alone, 
and that there is less complaint of 
headache and dizziness after its admin¬ 
istration in this manner. This indicates 
that there is an increase in the safety 
of carbon tetrachloride administration 
when given with salts. 
The additional safety of anthelmin¬ 
tics when given with magnesium 
sulphate must be checked against 
another factor than inhibition of ab¬ 
sorption by virtue of the osmotic action 
occurring in the presence of salts. 
This is the factor of purgation itself. 
Hall ( 12 ) has noted that, contrary to a 
frequently repeated statement, it is not 
dangerous td give male fern with, 
castor oil. He cites experiments in 
which dogs given lethal doses of male 
fern with adequate doses of castor oil 
survived, whereas the same dose with¬ 
out the castor oil was* fatal. In 
human medicine various physicians, 
such as Leichtenstern ( 81 ), concur 
in this. Hall also reports an experi¬ 
ment in which the lethal dose of male 
fern given with 6 grains of calomel 
was not fatal to a dog. In the same 
paper he reports that dogs survived 
the administration of dangerously high 
to lethal doses of chenopodium with 
large doses of castor oil. Thus purga¬ 
tion alone by means of such purgatives 
as castor oil or calomel is highly pro¬ 
tective against anthelmintics, as clini¬ 
cal experience also indicates, and may 
of itself save an animal from .an other¬ 
wise lethal dose of an anthelmintic. 
On theoretical grounds, sustained by 
experimental evidence, the salt action 
of magnesium sulphate should add to 
this purgative action the inhibition of 
absorption by virtue of pronounced 
osmosis with fluids entering the lumen 
of the digestive tract. Even with 
this added action, magnesium sulphate, 
as one of the present experiments 
shows, may fail occasionally to save 
one animal from a lethal dose, although 
saving another animal from a dose at 
a higher rate. 
The further element of speed of action, 
must be considered in selecting pur¬ 
gatives in connection with anthel¬ 
mintics. There has been more or less 
