HOREHOUND, WHITE Marrubium vulgare (LINN.)
N.O. Labiates
Synonym. Hoarhound
Part Used. Herb.
Habitat. White Horehound is a perennial herbaceous plant, found all over Europe and indigenous to Britain. Like many other plants of the Labiate tribe, it flourishes in waste places and by roadsides, particularly in the counties of Norfolk and Suffolk, where it is also cultivated in the corners of cottage gardens for making tea and candy for use in coughs and colds. It is also brewed and made into Horehound Ale, an appetizing and healthful beverage, much drunk in Norfolk and other country districts

Description. The plant is bushy, producing numerous annual, quadrangular and branching stems, a foot or more in height, on which the whitish flowers are borne in crowded, axillary, woolly whorls. The leaves are much wrinkled, opposite, petiolate, about I inch long, covered with white, felted hairs, which give them a woolly appearance. They have a curious, musky smell, which is diminished by drying and lost on keeping. Horehound flowers from June to September.

The Romans esteemed Horehound for its medicinal properties, and its Latin name of Marrubium is said to be derived from Maria urbs, an ancient town of Italy. Other authors derive its name from the Hebrew marrob (a bitter juice), and state that it was one of the bitter herbs which the Jews were ordered to take for the Feast of Passover. The Egyptian Priests called this plant the 'Seed of Horus,' or the 'Bull's Blood,' and the 'Eye of the Star." It was a principal ingredient in the negro Caesar's antidote for vegetable poisons.

Gerard recommends it, in addition to its uses in coughs and colds, to 'those that have drunk poyson or have been bitten of serpents,' and it was also administered for 'mad dogge's biting.� It was once regarded as an anti-magical herb. According to Columella, Horehound is a serviceable remedy against Cankerworm in trees, and it is stated that if it be put into new milk and set in a place pestered with flies, it will speedily kill them all.

Cultivation. White Horehound is a hardy plant, easily grown, and flourishes best in a dry, poor soil. It can be propagated from seeds sown in spring, cuttings, or by dividing the roots (the most usual method). If raised from seed, the seedlings should be planted out in the spring, in rows, with a space of about 9 inches or more between each plant. No further culture will be needed than weeding. It does not blossom until it is two years old.

Until recently, it was chiefly collected in Southern France, where it is much cultivated. It is in steady demand, and it would probably pay to cultivate it more in this country. White Horehound is distinguished from other species by its woolly stem, the densely felted hairs on the leaves, and the ten-toothed teeth of the calyx.

Constituents. The chief constituent is a '' bitter principle known as Marrubium, with a little volatile oil, resin, tannin, wax, fat, sugar, etc.

Medicinal Action and Uses. White Horehound has long been noted for its efficacy in lung troubles and coughs. Gerard says of this plant: 'Syrup made of the greene fresh leaves and sugar is a most singular remedie against the cough and wheezing of the lungs and doth wonderfully and above credit ease such as have been long sicke of any consumption of the lungs, as hath beene often proved by the learned physitions of our London College.'

Culpepper says: 'It helpeth to expectorate tough phlegm from the chest, being taken with the roots of Irris or Orris.. There is a syrup made of this plant which I would recommend as an excellent help to evacuate tough phlegm and cold rheum from the lungs of aged persons, especially those who are asthmatic and short winded.'

Preparations of Horehound are still largely used as expectorants and tonics. It may, indeed, be considered one of the most popular pectoral remedies, being given with benefit for chronic cough, asthma, and some cases of consumption. Horehound is sometimes combined with Hyssop, Rue, Liquorice root and Marsh-mallow root, � oz. of each boiled in 2 pints of water, to 1� pint, strained and given in � teacupful doses, every two to three hours.

For the ordinary cold, a simple infusion of Horehound (Horehound Tea) is generally sufficient in itself. The tea may be made by pouring boiling water on the fresh or dried leaves, 1 oz. of the herb to the pint. A wine-glassful may be taken three or four times a day.

Candied Horehound is best made from the fresh plant by boiling it down until the juice is extracted, then adding sugar before boiling this again, until it has become thick enough in consistence to pour into a paper case and be cut into squares when cool. Two or three teaspoonfuls of the expressed juice of the herb may also be given as a dose in severe colds.

Horehound has a perennial, fibrous root, and numerous erect, woolly stems, from twelve to eighteen inches high. The leaves are about 2.5 cm. long, roundish-ovate, crenate, wrinkled, downy above, hoary on the under surface, and supported in pairs on strong foot-stalks. The flowers are white, and in crowded -axillary woolly whorls. Each consists of a sparsely hairy, tubular calyx with 10 hooked, bristle-like teeth, a bilabiate corolla, 4 parallel stamens and a bi-carpellary pistil with a 4-celled ovary.

Horehound has been adulterated with the leaves and flowering tops of Ballota hirsuta Benth., Ballota nigra L., Marrubium peregrinum L. and Marrubium candidissimum L. From all of these it may be readily distinguished by its characteristic calyx. Battota hirsute has been the most common recent adulterant. For detailed structural differences between Marrubium and Ballota hirsuta see article by H. W. Youngken in A. J. P., 1919, pp. 147-156.

Horehound contains a volatile oil, resin, tannin, and a bitter principle called marrubiin. This marrubiin is slightly soluble in cold water, crystallizes from alcohol in prismatic and from ether in tabular crystals, is not precipitated by tannin, and has a very bitter and somewhat acrid taste. The fusing point of the crystals is 160� C., according to Kromayer. Matusow (A. J. P., 1897, 201). He gives to it the formula CaoHuOg, and states the melting point of the purified substance to be from 154 to 155� C. According to him, it is not a glucoside.

Hoarhound is tonic, and in large doses laxative. It was formerly considered a valuable deobstruent, and was recommended in chronic hepatitis, and various other affections but it exerts no influence over any of them, and has passed mainly from the hands of physicians into domestic use, where it is used in the form of a confection for sore throat. It is employed occasionally in bronchitis

with copious expectoration. The infusion, made in the proportion of an ounce of the herb to a pint of boiling water, may be given in wine-glassful doses.