614 AGENTS OF ANIMAL ORIGIN 



Action Internal, — Cantharides affects mainly the diges- 

 tive and genito-urinary tracts. It is a violent gastro-intes- 

 tinal irritant. Toxic doses cause vomiting, in animals 

 capable of the act, at first bilious (and containing gref^nish 

 specks of the wings and wing cases), then mucous, and finally 

 bloody. There is purging in' all, associated with great pain 

 and straining, of a mucous, fibrinous, and often haemorrhagic 

 character. There are salivation, swelling and pain in the 

 salivary glands. The gastro-enteritis is accompanied by 

 general prostration, and feeble, rapid pulse. A few hours 

 after the occurrence of the preceding symptoms there is 

 enough absorption of cantharidin to induce lumbar pain, 

 followed by frequent, scanty and painful micturition (stran- 

 gury). The urine is albuminous and often bloody. Can- 

 tharides is eliminated chiefly by the kidneys, but also to 

 some extent by the other excretory organs, including the 

 skin. Sexual excitement may be present in poisoning. It 

 is more common with small than large toxic doses. There 

 are erections and great heat in the penis, and even inflam- 

 mation and sloughing of the organ. Abortion is precipitated 

 in the pregnant, and " heat " is hastened in the non- 

 pregnant female. Stupor, coma, and collapse close the scene 

 after lethal doses. Twenty grains of cantharides have killed 

 a man ; forty, a dog ; and one drachm has destroyed a horse. 



The treatment includes the use of emetics or the stomach 

 pump ; opium, to relieve pain and strangury ; albuminous, 

 mucilaginous drinks ; and, in collapse, external heat, alco- 

 holic stimulants, strychnine ^nd atropine under the skin. 

 Oils and fats dissolve cantharidin and must not be given in 

 poisoning as demulcents. 



Post Mortem Appearances. — Swelling, congestion, ecchy- 

 moses, and erosion of the gastro-intestinal mucous membrane 

 are observed after death by cantharides. There are, more- 

 over, lesions of acute nephritis and cystitis, with inflam- 

 mation of the whole genito-urinary mucous membrane. 

 Hypersemia of the brain and spinal cord have also been 

 reported. 



