CANTHARIS VESICATORIA. 



ployment of them internally is sufficient to set aside their 

 general administration. 



When Cantharides have been accidentally taken in large 

 doses, the best mode of counteracting the dangerous symp- 

 toms is to administer emetics, to bleed, and to dilute copious- 

 ly with bland, demulcent drinks. The use of oil must be care- 

 fully avoided ; for as oil is the best solvent of cantharidin, the 

 poison is only the more widely diffused, and consequently it 

 is rendered more extensively hurtful. Many of the cases of 

 poisoning by Cantharides have arisen from the poison having 

 been swallowed with the view of exciting the venereal appe- 

 tite ; for, as in many cases this effect has not followed the or- 

 dinary dose, large doses have been swallowed. The greater 

 number of the cases detailed by toxicological writers have 

 not terminated fatally, although the sufferings of the patients 

 have been most severe. In some instances the inflammation 

 of the genital organs has run on to gangrene ; which was the 

 case in a fatal instance noticed by Ambrose Pare, which was 

 caused by a young woman seasoning comfits for her lover 

 with Cantharides. In some instances phrenitic symptoms, 

 with tetanic convulsions and hydrophobia, have been the con- 

 sequence of over-doses of the tincture. 



The emplastrum Cantharidis of the Pharmacopoeias, the 

 substance commonly applied for producing a blister, has some 

 disadvantages attending its employment. It consists of one 

 part of finely powdered Cantharides blended with one or two 

 parts of wax plaster. In the first place, the formation of the 

 plaster by heat injures the activity of the Cantharides ; in the 

 second place there is a great waste, as only those particles of 

 the powdered insect which are upon the surface are of use. 

 It would, therefore, be much better, were some kind of semi- 

 adhesive paste contrived for forming the basis of the plaster, 

 upon which the powdered Cantharides could be sprinkled 

 before applying the plaster to the skin. Were cantharidin 

 easily prepared, the most certain blister would be a solution of 

 that substance in oil ; but the tediousness of the process, and 

 the smallness of the product, render it impossible to employ 

 it for ordinary purposes. The plaster of Cantharides causes, 

 first, a sensation of heat and pricking in the part, attended 

 with some general excitement and increased quickness of the 

 pulse ; if it remain on a sufficient space of time, namely, from 

 six to ten hours, the cuticle is raised, and betwixt it and the 



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