Jalapa (Ipomoea jalapa)
The dried tuberous root of Ipomoea jalapa, Nuttall; (Ipomoea purga, Hayne; Exogonium jalapa, Baillon; Exogonium purga, Bentham). Nat. Ord. Convolvulaceae. A vine of Eastern Mexico. Dose, 10 to 30 grains.
Common Name: Jalap.
Principal Constituents.—A resin (Resina Jalapae) composed chiefly of Jalapurgin (C62H100O32) (convolvulin or jalapin) and a soft acrid resin.
Preparations.—1. Resina Jalapae, Resin of jalap. Yellowish-brown or brown masses or fragments, or a yellowish-gray or yellowish-brown powder, permanent, of a faint but peculiar odor, and somewhat acrid to the taste. Soluble in alcohol. Dose, 2 grains.
2. Pulvis Jalapae Compositus (U. S. P.), Compound Powder of jalap. (jalap, 35; Potassium Bitartrate, 65.) Dose, 20 to 60 grains. (Locke advises Ginger, 3 drachms, in 8 ounces of this preparation to prevent griping.)
3. Pulvis Jalapae Compositus (Eclectic), Compound Powder of jalap (Eclectic), or Antibilious Physic. (Senna, 2 ounces; Jalap, 1 ounce; Cloves or Ginger, 1 drachm.) Dose, 60 grains (in hot water allowed to cool and then sweetened).
4. Specific Medicine Jalap. Dose, 5 to 20 drops.
Specific Indications.—Intestinal torpor and constipation from deficient secretion of the intestinal glands; pain and griping in the lower bowel.
Action and Therapy.—Jalap is an irritant cathartic operating energetically and producing large liquid stools. It gripes considerably and sometimes causes nausea and vomiting. Large doses produce violent hypercatharsis, sometimes resulting in death. It is a safe and thorough cathartic when no inflammation of the gastro-intestinal tract exists, and may be used where a derivative action, with full stools, is indicated. In small doses (5 grains daily) it may be employed to relieve constipation due to inactivity of the intestinal glands or where hard fecal masses are impacted in the rectum. Movements are facilitated by the secretion induced. It is a useful revulsive in cerebral congestion, and may be used in hemorrhoidal conditions with constipation when a stimulating cathartic cannot be employed.
The chief use of jalap is for the relief of dropsy from any cause. It is commonly used with cream of tartar, which increases both the cathartic and diuretic effects. It should not be given for any great length of time, for the depletion finally has a depressing effect upon the heart. Though contraindicated in inflammation of the intestinal tube, it may be used when there is inflammation of the biliary apparatus, and when a cathartic is needed at the onset of fevers. The Antibilious Physic and that modification of the compound powder as advised by Locke are desirable forms in which to use jalap. Jalap alone purges in about 3 to 4 hours.
The Eclectic Materia Medica, Pharmacology and Therapeutics, 1922, was written by Harvey Wickes Felter, M.D.