Hygrophila consists of the dried herb, including the root, of Hygrophila spinosa, T. And. (N.O. Acanthaceae), a native of India. The plant has tapering roots with numerous rootlets and erect bluntly quadrangular stems, which are swollen at the nodes and bear opposite leaves and branches. There are six entire leaves at each node, the. two outer ones being 10 to 13 centimetres long and 12 millimetres broad; the four inner ones are 4 centimetres long, linear lanceolate, and tapering. A brownish spine, about 2.5 centimetres long, occurs in the axil of each leaf. The stem and leaves are more or less covered, especially near the nodes, with stiff three to five-celled hairs. Four pairs of awl-shaped flowers occur at each node, the bracts resembling the leaves in shape. The calyx has four sepals, one being broader than the others. The corolla is glabrous and two-lipped, with didynamous stamens and an oblong staminode on the lower lip. The fruit contains four to eight brownish, flattened seeds, about 2 to 3 millimetres long and 1 to 1.5 millimetres broad. When moistened the seeds exude a large quantity of a tenacious mucilage. The drug has no distinct odour or taste.
Constituents.—The chief constituent of hygrophila is mucilage. The plant also contains traces of an alkaloidal substance, together with phytosterol, and fixed oil.
Action and Use.—Hygrophila is official in India and the Eastern Colonies; a decoction of the drug is prepared for use as a demulcent and mild diuretic in catarrh of the urinary organs.
- Decoctum Hygrophilae, I.C.A.—DECOCTION OF HYGROPHILA.
- Hygrophila, cut small, 10; distilled water, sufficient to produce 100. Add the drug to 300 of the water, boil until the liquid is reduced to 100, strain, and make up to the required volume if necessary by passing distilled water through the strainer. Decoction of hygrophila is official in India and the Eastern Colonies, where it is used as a demulcent and diuretic, similar in its properties to decoction of couch grass. Dose.—15 to 60 mils (1/2 to 2 fluid ounces).
The British Pharmaceutical Codex, 1911, was published by direction of the Council of the Pharmaceutical Society of Great Britain.