Pulvis Jalapae Compositus. U. S., Br. Compound Powder of Jalap.

Botanical name: 

Pulv. Jalap. Co. [Pulvis Purgans]

Related entry: Jalapa

Pulvis Purgans, Pulvis Jalapae Tartratus, Pulvis Catharticus; Poudre de Jalap composee, Fr.; Jalapenpulver mit Weinstein, G.

"Jalap, in No. 60 powder, thirty-five grammes [or 1 ounce av., 103 grains]; Potassium Bitartrate, in fine powder, sixty-five grammes [or 2 ounces av., 128 grains], to make one hundred grammes [or 3 ounces av., 231 grains]. Mix the powders intimately by trituration and pass the product through a No. 60 sieve." U. S.

"Jalap, in powder, 30 grammes; Acid Potassium Tartrate, in powder, 60 grammes; Ginger, in powder, 10 grammes. Mix." Br.

Properties.—"Very light brown; when examined under a microscope it exhibits numerous, sharp-angular, colorless fragments mostly somewhat rectangular and with straight edges varying from 0.03 to 0.3 mm. in length, slowly soluble in water or hydrated chloral T.S. and polarizing light with a strong display of colors (fragments of crystals of potassium bitartrate), numerous starch grains of jalap, readily distinguished without the use of iodine T.S., usually single, occasionally 2- to 3-compound, and varying from 0.003 to 0.035 mm. in diameter; occasional fragments of laticiferous vessels and parenchyma with yellowish-brown walls, or tracheae with bordered pores, and rosette aggregates of calcium oxalate from 0.01 to 0.035 mm. in diameter, that occur in jalap." U. S.

The rubbing of the bitartrate with the jalap is thought to favor its more minute division, while it increases its hydragogue effect. A combination of these two ingredients, though with a larger proportion of cream of tartar (see Jalapa), forms a good cathartic in dropsy.

Dose, of the powder, from thirty grains to a drachm (2.0-3.9 Gm.).


The Dispensatory of the United States of America, 1918, was edited by Joseph P. Remington, Horatio C. Wood and others.