Botanical Source.—This is an erect, perennial herb, about a foot high, found growing in creeks and wet situations throughout the United States and Canada. The stem is smooth, round at the base, but angular above, and often branched. It has numerous scattered, thin leaves, from 2 to 3 inches long, about 1/3 as wide, and attached to the stem at an acute angle. They are lanceolate, smooth, finely and sharply serrate, tapering regularly to an acute apex. and at the base to a very short leaf-stalk. The flowers are small, inconspicuous, and arranged in terminal naked cymes, consisting of from 2 to 4 slender, simple, 1-sided branches, which unroll as the flowers expand. The flowers are supported on short peduncle., about 1/8 of an inch long, and consist, each, of a 5-parted calyx, 10 stamens, and 5 pistils, which are united at the base. The petals are generally wanting. The fruit consists of 5 dry, 1-celled capsules, beaked with the persistent style, and united at the base. They open, when ripe, at the summit, and are filled with numerous minute seeds. The genus Penthorum, which differs from its allies of the Crassulaceae in not having fleshy stems, consists of only 2 species-the one described above, indigenous to North America, the other found only in China.
History and Chemical Composition.—Penthorum sedoides was mentioned by some of the older authorities, but its more recent introduction into medicine may be ascribed to Dr. F. H. Briggs (Ec. Med. Jour., 1875, p. 479). The fresh herb has an astringent, slightly acid taste, and, when bruised, an herb-like odor. The properties of the fresh plant are best extracted by alcohol, and seem chiefly to depend upon a form of tannin which, in alcoholic solution with ferrous sulphate, first turns blue and then precipitates black. With ferric sulphate, it forms a deep-green solution. Neither the tincture, nor the tincture freed from tannin, shows the slightest indication of an alkaloid with the ordinary reagents. When the herb is distilled with water, the distillate is free from volatile oil.
Action, Medical Uses, and Dosage.—Dr. Briggs states that "the older authorities gave this agent as a demulcent and laxative, and it does not seem to exert the astringent action common to agents containing tannic acid. The impression upon the mouth is that of an astringent, but, on examining the mucous membrane, it does not seem corrugated, but very fresh and rosy, and it would undoubtedly prove a valuable tooth and mouth wash." The fluid extract and specific medicine have been employed successfully in the treatment of cholera infantum, diarrhoea, and hemorrhoids. Prof. J. M. Scudder observes that mucous membranes, especially when they have suffered from inflammatory action, are peculiarly influenced by this agent, which gradually removes irritation, promotes normal functional activity, and restores the tissues to their normal condition. He found it not only an excellent remedy in diarrhoea, but likewise in chronic nasal catarrh, in chronic pharyngitis, in chronic bronchitis, with increased secretion, and in chronic vaginitis, with or without leucorrhoeal discharge. He employs it internally and locally, when this can be effected, in spray; also as a topical application to chronic ulcers. It is not, as a rule, as well adapted to acute as to chronic disorders, and must be used for a length of time to obtain its best effects. As a reliever of irritation of mucous surfaces, its best results have been obtained in chronic affections of the posterior nares, pharyngeal vaults, and Eustachian tubes. It may be used both internally and by atomization. It has been of benefit in indigestion and nervous dyspepsia. Its effects upon the gastric membranes have been compared to those of small doses of ipecac. The dose of the fluid extract is from 10 to 60 minims, repeated every 3 or 4 hours; of the specific penthorum, 1 to 30 minims, in a teaspoonful of water. Penthorum is a remedy of undoubted power, and deserves a more careful study than has been hitherto bestowed upon it. It is best adapted to chronic conditions, being of little service in acute phases.
Specific Indications and Uses.—Pharyngeal and nasal disorders of a chronic type, with fullness, dryness, and irritation, with a purplish, congested appearance; catarrhal inflammations, with profuse secretions; catarrhal gastric disorders; catarrhal diarrhoea; spongy gums.
King's American Dispensatory, 1898, was written by Harvey Wickes Felter, M.D., and John Uri Lloyd, Phr. M., Ph. D.