644 AGENTS OP ANIMAL ORIGIN 



PREPARATIONS. 



Tindura Gantharidis. Tincture of cantharides. (TJ. S. & B. P.) 

 Made by percolation of cantharides, 100 ; with alcohol to make 

 1000. (U, S. P.) 



Dose.— H. & C, 3ii.-iv. (8.-15.); D., T7lii.-xv. (.13-1.). 



Ceratum Cantharidis. (TJ. S. P.) 

 Gantharidis powdered, 320 ; petrolatum, wax, rosin and lard to 

 make 1000. 



Unguentum Cantharidis. (B. P.) 



Action External. — Cantharides, by virtue of cantharidin, 

 is an intense irritant. When applied to the skin in ointment 

 it produces no effect for several hours, but after that time 

 causes dilatation of the cutaneous vessels, hypersemia, and 

 blisters, which appear in from 3 to 12 hours. The blisters 

 soon break, discharge their serous contents, and then dry 

 and crust the surface. If the action of cantharides is main- 

 tained continuously ; if the , application is repeated, or 

 covered with a bandage ; or if the skin was previously 

 inflamed, then inflammation of the deeper-seated parts 

 ensues, followed by suppuration, sloughing, loss of tissue, 

 destructipn of hair follicles, and scars. The drug is thera- 

 peutically a rubefacient and vesicant, and counter-irritant, 

 in occasioning dilatation of the superficial vessels, and 

 reflexly, contraction of those in the remote underlying parts. 

 Cantharides acts more powerfully on the skin of horses and 

 dogs, than on that of cattle and swine. If applied over an 

 extensive surface, absorption and poisoning may occur. 



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 greenish 

 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 hsemorrhagie 

 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 



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