338 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VI, IV

        Discussion on the dosage of antimony tartarate and its dilution

Only very meagre information is available in text-books on Veterinary
Pharmacology and Toxicology regarding the therapeutic dose of this drug and
its dilution for intravenous use in cattle. Some amount of information is avail-
able, however, in papers on the treatment of flystruck cattle in Africa contributed
by Hornby [1919, 1921]. He seems to have used 1.6 to 2 grains per 100 lbs. body-
weight. Edwards [ 1929 ] commenting on the work of Das, says that at Muktesar,
cattle tolerate doses of 5 c.c. of a 3 per cent solution (or 2.25 grains per 100 lbs.
body-weight), that this dose can be repeated daily for about 10 days and that
it is not safe to increase this dosage, though cattle may tolerate double that dose
for three days. Even with 2.25 grains per 100 lbs. body-weight, Edwards says
that accidents may follow. From our experiments, it is gathered that a dose
which causes a reaction is a sub-lethal dose. Hence, the therapeutic dose should be
much less than the sub-lethal dose and considerably so. if it is to be repeated at
short intervals for the reason that the drug is more or less cumulative. Our
experiments show that a dose of 1.5 grains per 100 lbs. body-weight, given daily
for six days, is not harmful in any way and at the same time, the desired results
are obtained.

From the published records of previous workers, it is not possible to calculate
the doses they gave per unit of body-weight since none of them excepting Das,
seems to have noted the weights of the animals treated. Doraiswami [ 1934 ]
and Iyengar [ 1934 ] appear to be the only two, who computed the dose of the
drug according to the body-weight of the animals they treated. The former
gave 3 or 4 grains while the latter only 1.25 grains per 100 lbs. body-weight.
Iyengar goes further in saying that the dose can be reduced to one grain per unit of
body-weight without losing the efficacy of the treatment. Edwards [ 1928 ] found
that the minimum lethal dose of tartar emetic to hill cattle is 14 c.c. of M-10 solu-
tion or just over 5.5 grains per 100 lbs. body-weight. Our experiments confirm
this.

As regards the dilution of the drug for intravenous use in cattle, there have
been differences of opinion among the previous workers. It would appear, that
they used solutions ranging from 2 to 15 per cent in strength, presumably without
any ill-effects. Krishnamurthi [ 1922] said that a powerful drug like antimony
tartarate should be given in the form of a 2 per cent solution and administered
20 grains of the drug in that dilution, but the animal collapsed and died 12 hours
later. Das [ 1929 ] injected 15.5 grains in 50 c.c. of water (nearly 2 per cent solu-
tion) in an animal weighing 440 lbs. (or 3.5 grains per 100 lbs. body-weight) and it
died soon after. Pillai [1934] recommended a different plan of action. He chose
to give 10 to 20 grains of the drug, presumably in 20 c.c. of saline or water (3 - 3 to
6.6 per cent solution) and injected it into the jugular vein, very slowly, taking
over five minutes to complete the operation, so as to allow further dilution of
the solution in the blood before it reached the heart. With this procedure, he says,
he met with no accidents of any sort. It is doubtful, if such a length of time for