Althaea officinalis is an herbaceous perennial, with a perpendicular branching root and erect woolly stems, from two to four feet or more in height, branched and leafy towards the summit. The leaves are alternate, ovate to slightly cordate, toothed, often 3-lobed and of velvety texture. The flowers are terminal and axillary, with short peduncles, each bearing one, two, or three flowers. The calyx is surrounded by a six to nine cleft involucel. The corolla has five spreading, obcordate petals, of a pale rose color. The fruit consists of numerous capsules united in a compact circular form, each containing a single seed. The plant is native to Europe, inhabiting salt marshes, the banks of rivers, and other moist places. It is found also in this country, from New England to New York and westward to Michigan and Arkansas. It is largely cultivated in Europe for medicinal use, particularly in Germany, Holland, Belgium and France. These countries supply most of the drug used in the United States. The roots should be collected in autumn from plants at least two years old. They are usually prepared for the market by removing the outer layers. The commercial drug sometimes consists of the unpeeled root, which is sliced transversely and diagonally.

Description and Physical Properties.� The root, which is recognized by the U. S. P., is described as follows:

Unground Althea.�Slenderly tapering, when entire up to 30 cm. in length and 2 cm. in thickness, usually cut into small pieces, about 5 mm. in diameter; externally whitish, longitudinally furrowed, frequently spirally twisted and covered with somewhat loosened bast-fibers; fracture of bark fibrous, of wood short and granular; internally yellowish-white; bark 1 to 2 mm. thick, porous, due to mucilage cells, and separated from the slightly radiating wood by a distinct grayish cambium zone; odor slight; taste sweetish, mucilaginous.

Powdered Althea.�Starch grains numerous, up to 0.03 mm. in diameter, usually with a long central cleft; groups of fibers with thick, more or less lignified walls; tracheae with scalariform thickenings or with bordered pores; calcium oxalate crystals few, in rosette aggregates, 0.020 to 0.035 mm. in diameter.

Add 1 Gm. of Althea to 10 cc. of cold water, allow it to stand with occasional stirring during thirty minutes, and filter through purified cotton: a pale yellow-colored mucilage is obtained, which is neutral to litmus paper and is colored a deep yellow on the addition of a few drops of sodium hydroxide T.S. The mucilage does not have a sour or ammoniacal odor." U. S.

The drug contains on the average 37 per cent, of starch, 35 per cent, of mucilage, 11 per cent, of pectin, 11 per cent, of sugar, 1.25 per cent, of fat and up to 2 per cent, of asparagin. The abundant mucilage is situated chiefly in special cells, and can be seen to be in layers when alcohol is added. Kraemer (A. J. P., 1898, p. 285) proposed the use of an alcoholic solution of methylene blue for the differentiation of the mucilage. It, with starch and saccharine matter, is taken out by boiling water. The gum may be extracted, without the starch, by coFd water and forms a ropy mucilage.

The principle discovered in the root by Bacon, by him called althein, has been ascertained to be asparagin. This substance belongs to the group of amides and hence has been called asparamide. When decomposed it breaks up into ammonia and aspartic acid, C₄H₇NO₄, and one molecule of the resulting ammonium aspartate corresponds with one molecule of asparamide and one of water. (J. P. C., xix, 208.) Asparagin, being now recognized as a derivative of succinic acid, is called amido-succinamide, and the aspartic acid is called amido-succinic acid. It is found in various other plants besides the marshmallow, as in the shoots of asparagus, in vetches grown in the dark, in all the varieties of the potato, and in the roots of the comfrey and licorice plant. According to Pira, asparagin has acid properties. It has no therapeutic value. Betaine has been obtained from althea by Orlow. (Ph. Z. E., 1898.)

The roots of other Malvaceae are sometimes substituted for that of marshmallow, without disadvantage, as they possess similar properties. Among these are Althaea rosea Cav., or hollyhock, and Malva Alcea L. The dark purple flowers of a variety of A. rosea have been proposed as a test for acids and alkalies . A strong infusion of these flowers imparts to slips of white filtering paper a permanent purplish-blue color, which is reddened by acids, and rendered bluish-green by alkalies.

ALTHEA or MARSHMALLOW LEAVES, under the title of Althaeas Folia, are official in the National Formulary. They are collected in June or July, while the plant is in flower, and dried. They are described in the N. F. as follows:

Description and Physical Properties.� Unground Althea Leaves. � Crumpled or matted; gray-green or yellowish-gray-green; densely and finely tomentose throughout; petioles 1 to 6 cm. long; blades 3 to 15 cm. long and 3 to 10 cm. wide, thin, cordate or rhomboidal-ovate in outline, rounded or nearly truncate at the base, acute at the apex; margin doubly serrate-dentate, the principal teeth from 1 to 3 pairs, the lowest almost large enough to be regarded as lobes, the secondary very irregular, triangulate, acute, broader than long, the sinuses acute; 2 to 6 principal veins originating with the midrib in the petiole, prominent underneath, terete; branches of midrib arising at a wide angle, nearly straight, each terminating in a marginal tooth. Odor slight, scarcely characteristic; taste mucilaginous.

Powdered Althea Leaf. � Grayish to grayish-green; numerous unicellular, non-lignified, stellate clustered hairs, up to 0.600 mm. long, usually in clusters of 2 to 6; few, short stalked, multicellular glandular hairs; calcium oxalate in rosette aggregates up to 0.030 mm. in diameter; epidermal tissue with stomata, the latter up to 0.037 mm. in length; few lamellated mucilage cells; pollen grains, few, spherical, spiny, up to 0.125 mm. in diameter." N. F. Marshmallow leaves, like the root, are used for their mucilage which is, however, less abundant than in the root.

Uses.� The virtues of marshmallow are exclusively those of a demulcent. The decoction of the root is much used in Europe in irritation and inflammation of the mucous membranes. A syrup of althaea is official in the German Pharmacopeia, and was introduced into the U. S. Pharmacopoeias of 1880 and 1890 (see U. S. D., 18th edition, p. 1327). Owing to its tendency to ferment rapidly it was not retained in the U. S. P., but is found in the N. F. V. (See Syrupus Altheae.) The roots themselves, as well as the leaves and flowers, boiled and bruised, are sometimes employed as a poultice. Its most important use is as an excipient for pills. It enters, as, an ingredient, into one mass and two pills of the U. S. P.

Dose of the leaves one-half to one drachm (2 - 4 Gm.).

Off. Prep.� From the root: Syrupus Althaeas, N. F. From the leaves: Species Emollientes, N. F.

If you did not find what you were looking for please use the site search box at the top right hand of the page, or else browse the site library and plant thumbnails.