Synonyms.—Marshmallow Root; Guimauve.
Althaea is the dried, peeled root of Althaea officinalis, Linn. (N.O. Malvaceae), a perennial plant, widely distributed in Central and Southern Europe. It is cultivated for medicinal use in Germany, France, and Belgium. The roots are collected in the autumn from plants not less than two years old, trimmed and scraped to remove the cork, and finally dried. They are sometimes split longitudinally, or cut into transverse slices, The drug is official in the U.S.P. It occurs usually in yellowish-white, straight, tapering pieces, from 10 to 15 centimetres long and 10 to 15 millimetres in diameter, bearing deep and broad longitudinal furrows. The surface is softly fibrous and bears the brownish scars of lateral rootlets. Internally the root is whitish and starchy. The transverse section exhibits a somewhat thick cortex, separated from the wood by a darker cambium line. On moistening the cut surface the radiate structure of both wood and cortex becomes visible, and cells containing mucilage can also be observed. The drug has a faint odour and a mucilaginous taste. It is occasionally limed to improve its appearance. Powdered marshmallow root is characterised by the presence of abundant bast fibres, starch grains, and mucilage cells. The bast fibres are long, narrow, and tapering, and have moderately thick walls; the starch grains are mostly simple and oval in shape, measuring 4μ to 15μ in length; the mucilage cells are stained deep red with a solution of ruthenium red and lead acetate.
Constituents.—The chief constituent of marshmallow root is mucilage, of which it is said to contain from 25 to 35 per cent. It also contains asparagin, starch, sugar, pectin, and a substance allied to lecithin.
Action and Uses.—Althaea is demulcent and emollient. Taken internally it is a popular remedy for catarrhs and bronchitis. It may be given in the form of syrup, lozenges, or decoction. Guimauve pastilles, which contain althaea, flavoured with neroli oil, are a useful and pleasant demulcent. The powdered root is useful as an excipient for pills which require some inert absorbent substance. Althaea has been applied to inflamed tissues as a fomentation (1 part of powdered root to 5 parts of water), the macerated drug being used as a poultice; and has been recommended as an ointment in a variety of skin diseases. Marshmallow ointment, properly so called, was prepared by heating marshmallow leaves with an equal weight of lard and straining, the product being employed for its soothing and emollient effects; the "marshmallow ointment" commonly sold, however, is simply a mild resin ointment, prepared without marshmallow.
- Decoctum Althaeae, B.P.C.—DECOCTION OF ALTHAEA. Syn.—Decoction of Marshmallow Root. 1 in 20.
- A popular remedy for coughs and bronchitis; it has valuable demulcent properties, and is useful generally in catarrhs of the mucous surfaces. Dose.—30 to 120 mils (1 to 4 fluid ounces).
- Syrupus Althaeae, B.P.C.—SYRUP OF ALTHAEA. Syn.—Syrup of Marshmallow Root. 1 in 25.
- Used as a demulcent. Dose.—2 to 8 mils (½ to 2 fluid drachms).
- Trochisci Althaeae, B.P.C.—ALTHAEA LOZENGES. Syn.—Marshmallow Lozenges. 1 grain.
- Used as a demulcent to allay cough.
- Unguentum Althaeae, B.P.C.—ALTHAEA OINTMENT. Syn.—Marshmallow Ointment.
- Prepared by boiling 2 of althaea leaves with 40 of water, evaporating to a thin extract, and incorporating with 4 of lard. This ointment should be freshly prepared as required.