Piscidia is the root bark of Piscidia Erythrina, Linn. (N.O. Leguminosae), a shrub found in South America and the West Indies, where it is used as a fish poison. The bark occurs in quills or curved pieces, from 5 to 15 centimetres in length, and from 4 to 6 millimetres in thickness. It is orange-brown to dark greyish-brown externally, wrinkled with thin longitudinal and transverse ridges, and somewhat fissured. The inner surface is brownish, and smooth or fibrous. The bark breaks with a tough, fibrous fracture, showing greenish patches. It has a characteristic odour, and a bitter, somewhat acid, taste.
Constituents.—The chief constituents of the bark are resin, fat, a crystallisable substance named piscidin, and a bitter glucoside which is soluble in water.
Action and Uses.—Piscidia dilates the pupil, but its action has not yet been clearly defined. It is a general sedative, and has been used for toothache, neuralgia, irritant coughs, and as an antispasmodic in asthma; also in dysmenorrhoea and nervous debility. It is administered in the form of extract or liquid extract.
- Extractum Piscidiae, B.P.C.—EXTRACT OF PISCIDIA.
- Dose.—6 to 30 centigrams (1 to 5 grains).
- Extractum Piscidiae Liquidum, B.P.C.—LIQUID EXTRACT OF PISCIDIA. 1 in 1.
- Has a sedative action, and has been recommended as a narcotic, being said to cause neither headache nor constipation. Dose.—2 to 8 mils (½ to 2 fluid drachms).