This section is from the book "Materia Medica Pharmacy, Pharmacology And Therapeutics", by W. Hale White. Also available from Amazon: Materia Medica Pharmacy, Pharmacology And Therapeutics..
Marrubium - Synonym. - Horehound. The leaves and tops of
Marrubium vulgare Linne (nat. ord. Labiatae).
Europe, Central Asia; naturalized in North America; cultivated.
Leaves about 25 mm. long, opposite, petiolate, roundish-ovate, obtuse, coarsely crenate, strongly rugose, downy above, white-hairy beneath; branches quadrangular, white, tomentose; flowers in dense, axillary woolly whorls, with a stiffly ten-toothed calyx, a whitish, bilabiate corolla, and four included stamens; aromatic and bitter.
Dose, 1 to 2 dr.; 4. to 8. gm.
Uses and Action of Horehound.
Horehound, used as a decoction or an infusion, is in moderate doses a diuretic, in large doses laxative, and may be so given as to increase the action of the skin and kidneys; but its action is not marked. It is probably also a bitter stomachic. Confection of horehound slowly dissolved in the mouth relieves the relaxed throat of public speakers.