Emplastrum Aromaticum. Dublin. Aromatic Plaster

"Take of frankincense, three ounces; yellow wax, half an ounce; cinnamon bark in powder, six drachms; oil of pimenta, oil of lemons, of each two drachms. Melt the frankincense and the wax together, and strain the mixture; when it thickens by cooling, mix with it the powder of cinnamon previously rubbed with the oils, and form them into a plaster."

This plaster, which is an elegant stimulant, is applied on the region of the stomach in dyspepsia, to allay pain and vomiting, and to expel flatus. As the oils are very volatile, it must be spread with the thumb, without being melted. It requires to be frequently renewed.

Emplastrum Assafoetidae. Edin. Assafoetida Plaster

" Take of plaster of semivitreous oxide of lead, assafoetida, of each two parts; galbanum, yellow wax, of each one part."

This plaster is sometimes applied over the umbilical region, in flatulence and hysteria.

Emplastrum Belladonnae. Lond. Dub. Plaster of Belladonna

"Take of plaster of resin, three ounces; extract of belladonna, an ounce and a half. Add the extract to the plaster, melted by the heat of a water bath, and mix.'7

This is an useful local application in cases of chronic pains, and applied to the sacrum in dysmenorrhoea.

Emplastrum Calefaciens

Dub. Warm Plaster. "Take of plaster of cantharides, one part; Burgundy pitch, seven parts. Melt them together with a moderate heat, and mix them so as to form a plaster."

This plaster is stimulant and rubefacient, and is applied with advantage in bronchitis, hooping-cough, sciatica, and local pains. The proportion of plaster of cantharides is rather too great, as it seldom fails to blister or produce a running sore, in many persons.

Emplastrum Cantharidis. Loud. Blistering Plaster

"Take of cantharides, rubbed to a very fine powder, a pound; wax plaster, a pound and a half; prepared lard, a pound. Sprinkle the cantharides in the plaster and the lard, melted together and removed from the fire when just about to become solid, and mix the whole together."

Emplastrum Cantharidis vesicatoriae, Edin. Blistering Plaster,

"Take of mutton suet, wax, white resin, blistering flies, reduced to a very fine powder, of each equal weights. Mix the powder with the other articles previously melted together, and removed from the fire; then stir until the mixture stiffens in cooling."

Emplastrum Cantharidis, Dub. Blistering Plaster.

"Take of purified yellow wax, mutton suet, of each a pound; yellow resin, four ounces; blistering flies, in fine powder, a pound. Melt the wax, the suet, and the resin together, and a little before they concrete in becoming cold, sprinkle in the blistering flies, and form the whole into a plaster."

Syn. Emplatre de Cantharides (F.), Kanthariden pflaster (G.), Emplastro di Cantarelle (I.).

These plasters are of a moderately soft consistence, so as to admit of being spread without the assistance of heat, which detroys the acrimony and epispastic property of the flies: they seldom fail of raising a blister if the cantharides be good, and have not been added when the other ingredients were too hot. When they are to be used, a piece of leather, of a proper shape and size, is first spread with adhesive plaster, and over this the blistering plaster is extended, of a moderate degree of thickness and as smooth as possible, by means of the thumb; a proper margin being left, so as to enable it to adhere closely to the skin; but a blistering plaster should not be bandaged down. There is, however, in this method of using cantharides, a waste of flies, as those only which are on the surface of the plaster, when it is spread, act on the skin; and it has been suggested by Parmentier1, that the same effect would be more economically produced by sprinkling the powdered flies on a piece of farinaceous paste, spread on linen or leather.

Blistering plasters require to remain applied for twelve hours, to raise a perfect blister; they are then to be removed, the vesicle is to be cut at the most depending part, and, without removing the cuticle, the vesicated part is to be dressed with simple cerate or spermaceti ointment, spread on lint; and the old cuticle allowed to remain until a new one is formed under it, when it peels off, and the whole is healed in the course of a few days. The application of these plasters, however, is sometimes attended with strangury and bloody urine, which arise from the canthariden being absorbed, and irritating the kidneys and urethra. This effect is much increased if the blister be applied over an abraded surface, as, for example, on the head immediately after it has been shaved; and it also occurs if the plaster remain too long applied. To prevent strangury, camphor has been recommended to be mixed with the blistering composition, but it has no good effect; and the action on the urinary organs is better obviated by copious dilution with milk, or mucilaginous fluids, and fomentations of warm milk and water to the blistered part, after the removal of the plaster.

When the head is the part intended to be blistered, it should be shaved at least ten hours before the plaster is applied; and it is a good rule to interpose a thin piece of gauze, wetted with vinegar, between the vesicatory and the skin, applied smooth and very close over the plaster.

1 Annales de Chimie, xlviii.

In persons of delicate habits, and those labouring under some diseases of irritation, particularly children, the blistered part, instead of healing kindly, becomes a spreading sore : the cutis vera is destroyed, and the part cannot be healed until the irritability of habit which induced this unpleasant state is allayed. In such cases, the blistering plaster should not be allowed to remain on longer than is requisite to raise the cuticle: but if ulceration have commenced, the best local application is a warm emollient poultice; and bathing the denuded surface frequently with tepid milk and water; while at the same time cinchona bark is internally administered.