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A poultice, a soft magma or mush prepared by wetting various powders or other absorbent substances with oily or watery fluids, sometimes medicated, and usually applied hot to the surface; it exerts an emollient, relaxing, or stimulant, counterirritant effect upon the skin and underlying tissues.

A poultice or plaster.

A medicine applied externally, under the form of a thick pap. Cataplasms are formed of various ingredients, and for different objects. They may be anodyne, emollient, tonic, antiseptic, irritating, &c. A simple poultice acts only by virtue of its warmth and moisture. Mealy, fatty substances, leaves of plants, certain fruits, crumb of bread, &c., are the most common bases. The chief poultices which have been officinal are the following :-Anodyne- c. Cicutae, c. Digitalis. Antiseptic -c. Carbonis, c. Dauci, c. Fermenti, c. Acetosae, c. Cumini. Emollient-c. Lini, c. Panis, c. Mali maturi. Irritating-c. Sinapis, c. Sodii chloridi, c. Quercus Marinae. Tonic and Astringent-c. Alum, c. Goulard, c. of Roses. The Parisian Codex had some other officinal cataplasms :-1. Cataplas'ma anod'ynum, made of poppy and hyoscyamus. 2. Cataplas'ma emolliens, made of meal and pulps. 3. Cataplas'ma ad supporatio'nem promoven'dam, of pulps and basilicon. 4. Cataplas'ma rubefa'ciens vel antipleurit'icum, formed of pepper and vinegar. The only cataplasms, the preparation of which it is important to describe, are some of the following:-

A poultice.

n. [Greek] A poultice.