502 POISONS : THEIR EFFECTS AND DETECTION. [§ 659 . 
Taylor) an ounce. This would be generally equivalent to 15 mgrms. 
(•24 grain). Hence the fatal dose of cantharidin may be approximately 
stated as from 6 mgrms. upwards. But, on the other hand, recovery 
has taken place from very large doses. 
§ 659. Effects on Animals. —Animals are unequally susceptible to 
the action of cantharidin. For example, hedgehogs and swallows are 
able to take large relative doses with impunity. Ellinger has shown 
that the whole of the poison is excreted unchanged by means of the 
kidneys of the hedgehog, therefore the kidney cells must be highly 
resistant to cantharidin ; other “ kidney poisons,” such as potassic 
chromate, cause as much change in the hedgehog’s kidneys as in other 
animals, so that the immunity is one for cantharidin alone. The re¬ 
sistance is not absolute ; 0-1 grm. causes nephritis, and, in a few days, 
death. Radecki 1 found that cantharidin might even be injected, in 
quantities equal to 15-30 mgrms., into the blood of fowls without any 
injury, and frogs also seem to enjoy the same immunity ; while dogs, 
cats, and other animals are sensitive to the poison. Galippe ascertained 
that, after the injection of 5 mgrms. into the veins of a dog, there was 
exaltation of the sexual desire ; the pupils quickly dilated, the dog 
sought a dark place, and became sleepy. Animals when poisoned die in 
asphyxia from paralysis of the respiratory centre. Schachowa 2 made 
some observations on the effect of cantharides on the renal excretion of a 
dog fed daily with 1 grm. in powder. On the third day, pus corpuscles 
were noticed ; on the fifth, bacteria ; on the thirteenth, the urine con¬ 
tained a large quantity of fatty matters, and several casts ; and on the 
seventeenth, red shrivelled blood corpuscles were observed. 
Effects on Man. —Heinrich 3 made the following experiments upon 
himself :—Thirty living blister-beetles were killed, and digested, without 
drying, in 35 grms. of alcohol for fourteen days ; of this tincture ten 
drops were taken. There ensued immediately a feeling of warmth in 
the mouth and stomach, salivation, the pulse was more frequent than in 
health, there was a pleasant feeling of warmth about the body, and 
some sexual excitement lasting three hours. In half an hour there was 
abdominal pain, diarrhoea, and tenesmus, and frequent painful micturi¬ 
tion. These symptoms subsided in a few hours, but there was a want of 
appetite, and pain about the kidneys, lasting until the following day. 
In the second experiment, on taking 1 cgrm. of cantharidin, there were 
very serious symptoms of poisoning. Blisters formed on the tongue, and 
there was salivation, with great difficulty in swallowing, and a general 
feeling of illness. Seven hours after taking the poison there were 
frequent micturitions of bloody urine, diarrhoea, and vomiting. Twenty 
1 Die Cantharidin Vergift., Diss., Dorpat, 1806. 
1 Unter.s. iiber die Nieren, Diss., Bern, 1877 ; Comil, Gaz. Med., 1880. 
3 Sehroff, Zeitsehrift d. Ges. d. Aerzte in Wien, xiii. 56. 
