Common Horehound - Marrubium vulgare

• Family: (Mint family) ^[E-flora]
  
• Other Names: Horehound.^[E-flora]
  White Horehound [HMH Duke][PFAF]

Identification
"Marrubium vulgare is a PERENNIAL growing to 0.5 m (1ft 8in) by 0.5 m (1ft 8in).
It is hardy to zone (UK) 3 and is not frost tender. It is in flower from Jun to November, and the seeds ripen from Aug to October. The flowers are hermaphrodite (have both male and female organs) and are pollinated by Bees, self.The plant is self-fertile.
It is noted for attracting wildlife.
Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in nutritionally poor soil. Suitable pH: acid, neutral and basic (alkaline) soils. It cannot grow in the shade. It prefers dry or moist soil."^[PFAF]

General: "Perennial herb from a stout taproot, white-woolly; stems ascending, 30-100 cm long, 4-angled, generally several; thyme-scented, cultivated for tea, flavouring." ^{[IFBC-E-flora]}
Leaves: "Opposite, round to broadly egg-shaped, 2-5.5 cm long, about as wide, bases lobed to round, tips blunt, green and wrinkled above, white-woolly below, margins blunt-toothed; lower long-, upper short-stalked; uppermost leaves not much reduced." ^{[IFBC-E-flora]}
Flowers: "Inflorescence of broad, many-flowered axillary clusters; corollas tubular, whitish, 8-15 mm long, slightly exserted from calyces, lips 2, about equal, the upper lip erect and narrowly 2-lobed, the lower lip spreading with broadly rounded central lobe; calyces star-shaped with ring of long hairs in throat, soft-hairy, the tube 4-5 mm long, the teeth 10, narrow, eventually widely spreading, sometimes unequal, tips spine-hooked." ^{[IFBC-E-flora]}
Fruits: "Nutlets, 4 clustered together, egg-shaped, smooth." ^{[IFBC-E-flora]}

Hazards

• "Emmenagogue and uterotonic (AHP). Five cups may cause arrhythmia (APA). ... “Hazards and/or side effects not known for proper therapeutic dosages” (PH2). APA notes that, to my confusion and consternation, the FDA “banned horehound” from OTC remedies in 1989, finding no convincing support for efficacy. Their German counterparts approved the herb a year later for colds, coughs, and dyspepsia with its accompanying gas and anorexia (APA). The plant juice from white horehound is an irritant and may cause dermatosis (CAN). ... Lack of toxicity data and suggested cardioactive properties suggest it should not be taken in excessive doses. Larger doses are laxative (CAN). Contraindicated in cardiopathy, hypertension, and pregnancy (WAM). Large doses are possibly arrhythmigenic or laxative (AHP; WAM)." [HMH Duke]
• "Heart rhythm, blood pressure, and blood glucose levels affected by large doses.... Diabetes mellitus patients on allopathic medication to lower blood sugar should avoid [301]."^[PFAF]
  
• "Not to be used during pregnancy" ^[PDR] "Avoid during pregnancy and breast feeding" [301] ^[PFAF] "Because it is reputed to be abortifacient, and reputed to affect the menstrual cycle, its use in pregnancy and lactation is to be avoided (CAN)." [HMH Duke]

Edible Uses

• Leaves
• Though it' s a member of the mint family, if you chew a raw horehound leaf while hiking, you probably won't notice any strong minty flavor. Rather, it will be uniquely bitter. [Nyerges]
  
• Seasoning: "The leaves are used as a seasoning[27]." ^[PFAF]
  
• Beer: "Bitter and pungent, they are sometimes used to flavour herb beer or liqueurs[4, 183]. Horehound ale is a fairly well-known drink made from the leaves[4, 238]." ^[PFAF]"‘Haryhound’ was widely made into a beer and drunk as a spring tonic in East Anglia till the early twentieth century." ^[MPFT] "... [Used] in beer instead of hops, and horehound beer was an East Anglian specialty (Clair). Randall records how his mother would always put a sprig of horehound in her brew, to improve the flavour, and to improve appetite. In Dorset, horehound and wood sage boiled and mixed with sugar made a cooling drink called woodsage beer, which was drunk at harvest time (Dacombe)." ^{[DPL Watts]}
  
• Tea: "A mild pleasantly flavoured tea is made from the fresh or dried leaves[183], it is a favourite cough remedy[4, 46]." [PFAF] The dried or fresh leaves of horehound can be made into tea. [Nyerges]
  
• Harvesting: Horehound leaves should be gathered in the spring when the plant is young and the leaves are large. [Nyerges]
  
• Properties: The tea has a strong bitter mint flavor, improved greatly by adding honey. [Nyerges] "The leaves smell tangy when rubbed and contain musk juice, which taste bitter and hot." ^[PDR]
  
• Candy: This plant provides the raw ingredients for horehound candy which has long been sold in drugstores and markets as a mild cough drop. [Nyerges]
  
• Preparation: Cook (don't boil) one cup of the fresh herb (or 1/4 cup of the dried herb) with two cups of water for about 15 minutes. Strain. To each cup of liquid, add one cup of honey. Cook until the mixture thickens. Keep at a low heat or it will run over. Pour onto a cookie sheet and let it cool. Break (or scoop) off pieces as you need or want it. It is best to refrigerate it, since it tends to spread. This candy is pleasant as a snack or energy food on the trail, as well as being useful for sore throats. [Nyerges]

Other Uses

• Essential Oil: "Obtained from the plant and used as a flavouring in liqueurs[46]." ^[PFAF]
  
• Repellent: "The growing plant repels flies[201]."^[PFAF]
  
• Floral: The dried seed stalks are attractive in dried floral arrangements, alone or mixed with other wild vegetation. [Nyerges]
  

Medicinal Uses

"White horehound is a well-known and popular herbal medicine that is often used as a domestic remedy for coughs, colds, wheeziness etc[4, 254]." ^[PFAF] "Marrubium vulgare has long been favoured in both book and folk medicine as a remedy for sore throats, hoarseness, colds, coughs of all kinds, bronchitis and asthma, for which there are records from many parts of Britain and particularly Ireland." ^[MPFT] "The medicinal parts are the dried flowering branches, the fresh aerial parts of the flowering plant and the whole plant.^{" [PDR]}

• Herb: "The herb apparently causes the secretion of a more fluid mucous, readily cleared by coughing [254]." ^[PFAF]
• Harvesting: Horehound is a perennial herb whose leaves are best gathered during the spring before the flowers appear. [Nyerges] "Horehound herb consists of the fresh or dried, above-ground parts of Marrubium vulgare as well as their preparations. The plant is harvested during the flowering season from June to August. Fast drying is recommended." ^[PDR]
  
• Preparation: As a hot tea, horehound has been commonly used as a tonic, and for chronic sore throat, coughs, colds, and breathing problems associated with asthma. [Nyerges]
• "Candied horehound was made, too (Grieve. 1933). But the herb is best known in folk medicine. This horehound candy was popular in American medicine before it became popular as a confection (Lloyd). The leaf expectorant has always been used (as an expectorant) to cure coughs and colds (Vesey-Fitzgerald; Dacombe), and it is still used in lozenges to control a cough (Cameron). As long ago as the Anglo-Saxon period it was prescribed for colds in the head (Cockayne), and leechdoms of similar date are recorded for coughs (Dawson. 1934). Gerard, too, recommended the infusion, for it “prevaileth against the old cough”, and the syrup made from the leaves “is a most singular remedy against the cough and wheezing of the lungs …”.^{[DPL Watts]}
• Appetizer: Approved by Commission E: Dyspeptic complaints and Loss of appetite ^[PDR] "A tisane of this herb is often taken for weak stomach, lack of appetite, etc. (Flück), and horehound was remembered in Cheshire as the cure for loss of appetite (Cheshire FWI). Indigestion and dyspepsia, too, were treated with this preparation. Even the Navajo Indians were reported to use this herb for indigestion (Wyman & Harris), and it is certainly an American domestic medicine for dyspepsia still (Henkel). There is nothing new in this." ^{[DPL Watts]}
  
• "Unproven Uses: The drug is used for dyspepsia, loss of appetite, bloating and flatulence, and respiratory catarrh. In folk medicine, it is used internally for acute and chronic bronchitis, whooping cough, asthma, tuberculosis, pulmonary catarrh, respiratory infections, diarrhea, jaundice, debility and painful menstruation, and as a laxative in higher doses; externally for skin damage, ulcers and wounds, and as a gargle for mouth and throat infections." ^[PDR]
  
• "Homeopathic Uses: Inflammation of the respiratory tract." ^[PDR]
• "Homeopathic Dosage: 5 drops, 1 tablet or 1 0 globules every 30 to 60 minutes (acute) or 1 to 3 times daily (chronic); parenterally: 1 to 2 ml sc acute, 3 times daily; chronic: once a day (HAB1).^"[PDR]
• Dosages
• "Preparation: To prepare an infusion, pour boiling water over 1 to 2 gm of the drug; strain after 10 minutes. For a liquid extract, prepare as a (1:1 ) dilution with ethanol (20%)."^[PDR]
  
• "Daily Dosage: The average daily dose is 4.5 gm of the drug; 30 to 60 ml pressed juice.^"[PDR]
  
• "The infusion dosage is 1 to 2 gm of the drug taken up to 3 times daily. The liquid extract dosage is 2 to 4 ml 3 times daily.^"[PDR]
  
• Leaves & Young Flowering Stems: "The leaves and young flowering stems are antiseptic, antispasmodic, cholagogue, diaphoretic, digestive, diuretic, emmenagogue, strongly expectorant, hepatic, stimulant and tonic[4, 7, 9, 21, 165, 238]."^[PFAF]
  
• Bitter Tonic:
• Harvesting: "The plant is harvested as it comes into flower and can be used fresh or dried[238]. Effect: Increases the appetite and supports the function of the stomach[254]. It can also act to normalize heart rhythm[254]." ^[PFAF]
• Colds: "Horehound is a very valuable pectoral, expectorant and tonic that can be safely used by children as well as adults[4]. Preparation: It is often made into a syrup or candy in order to disguise its very bitter flavour, though it can also be taken as a tea[4]." ^[PFAF]
• Root: "The root is a remedy for the bite of rattlesnakes, it is used in equal portions with Plantago lanceolata or P. major [207]." ^[PFAF]
• Plant: "... an infusion of the plant is said to have been a common remedy for earache or a headache"^[MPFT]
• Unspecified:
• "In Cumbria ... it has been valued for nosebleeds."^[MPFT]
• "... a preparation has had the reputation of cleaning out the valves of the heart, and a tea has been drunk for rheumatism." ^[MPFT]
• "...horehound was used for all pains in the chest, and for lung disease. The Lacnunga prescribed a draught for lung diseases: “boil marrubium in wine or ale; sweeten somewhat with honey. Give it warm to drink after the night’s fast. And then let him lie on his right arm as much as he can” (Grattan & Singer). ^{[DPL Watts]}
  

Further Medicinal Uses

"Horehound has still more uses, one being as an application to wounds (Flück). In Africa, it is used for fevers, especially typhoid (Watt & Breyer-Brandwijk); the Navajo, too, used it to reduce fever (Wyman & Harris). In Wales, the infusion of the chopped herb is used both externally and internally for eczema and shingles (Conway). Oedema is another condition to be remedied with this plant. A 16th century recipe from France reads: “pisser, neuf matins sur le marrube avant que le soleil l’ait touché; et à mesure que la plante mourra, le ventre se desenflera” (Sebillot) – but that is a simple transference charm. It is a counter-poison, too, or rather it was thought to be one. There are a number of authorities, though, who were sure of it, the Lacnunga for one, and the Anglo-Saxon Apuleius, and into the 14th century, too (Henslow). Perhaps the strangest use was in a sleeping draught, used in the Fen country. It was made of white horehound and rue, followed by a good dose of gin mixed with laudanum. It is quoted as being a last resort means of stopping a mother giving birth on 1 May (an unlucky day). It just put her to sleep for twenty-four hours (Porter. 1969).^{" [DPL Watts]}

Pharmacology

"The bitter ingredients act as a gastric juice stimulant; marrubinic acid acts as a choleretic. In animal experiments, a significant increase of bile secretion was observed after administration of marrubinic acid and its salt. The main active principles, essential oil, diterpene-amaroids, tannins and flavonoids indicate that the drug would probably stimulate gastric juice secretion." ^[PDR]

"HOH extracts are antihydroxytryptamine; EO is an expectorant, schistosomicidal, and vasodilator. Marrubiin is an antiarrhythmic, but in higher doses may reverse, becoming arrhythmogenic (CAN)." ^{[HMH Duke]}

Phytochemicals

• Diterpene hitter principles: chief components marrubiin (0.1-1.0%), premarrubiin (0.1%) ^[PDR]
  
• Caffeic acid derivatives: including among others chlorogenic acid, cryptochlorogenic acid ^[PDR]
  
• Flavonoids: including among others chrysoeriol, vicenin II, lactoyl flavones, for example luteolin-7-lactate, apigenin-7- lactate ^[PDR]
  
• Volatile oil (traces): including among others camphene, pcymene, fenchene ^[PDR]

Cultivation

"White horehound is an easily grown plant that succeeds in most well-drained soils[200], though it flourishes best in a poor dry soil[1, 4]. Another report says that the plant flourishes best where there is plenty of nitrogen in the soil[274]. It prefers neutral to alkaline soil conditions[238] and requires a warm sunny position if it is to do well[14]. Often grown in the herb garden and sometimes cultivated commercially as a medicinal herb[4, 61]. If the plant is cut back after flowering it will normally produce a second crop of leaves[238]. The fresh leaves have a pronounced musky smell, though this is lost once the plant is dried[245]. A good bee plant[1]. White horehound is a good companion plant for growing near tomatoes[24]. The tomatoes crop for a longer period and also produce a heavier crop[201]." ^[PFAF]

"The plant has been used as a cure for cankerworm in trees[238]. No more details are given but it is probably a strong infusion of the flowering shoots, or the essential oil, that is used[K]."^[PFAF]

"The seed whorls can also be gathered and scattered in your yard at the end of winter when, the ground is damp. Chances are that some horehound will come up. Horehound plants need little care in the garden, for in the wild they do well in dry regions in even the poorest soils." [Nyerges]

Propagation

" Seed - sow April/May or August/September in a cold frame. Germination can be slow and erratic[200]. Prick out the seedlings into individual pots when they are large enough to handle and plant them out in the following spring[K]. Basal cuttings in late spring. Harvest the shoots with plenty of underground stem when they are about 8 - 10cm above the ground. Pot them up into individual pots and keep them in light shade in a cold frame or greenhouse until they are rooting well. Plant them out in the summer. Division in spring[1]. Larger clumps can be replanted direct into their permanent positions, though it is best to pot up smaller clumps and grow them on in a cold frame until they are rooting well. Plant them out in the spring." ^[PFAF]

Synonyms

• Marrubium apulum. ^[PFAF]
• Marrubium ballotoides. ^[PFAF]
• Marrubium germanicum. ^[PFAF]
• Marrubium uncinatum. ^[PFAF]

MARRUBIUM HOREHOUND

"Perennial herb. Stem: generally erect, generally branched, tomentose. Leaf: petioled to ± sessile; blade generally ovate to round, crenate or toothed. Inflorescence: head-like, in leaf axils. Flower: calyx 10-lobed in California, lobes spreading or recurved, sharp-pointed; corolla 2-lipped, upper lip entire to 2-lobed, lower lip 3-lobed; stamens 4, fertile, lower pair generally > upper pair, included in tube; style included, lobes ± equal. Fruit: nutlet tip truncate.
30 species: Europe. (Latin: from ancient Hebrew word for bitter juice) [Ryding 1998 Syst Bot 23:235–247] Some species cultivated for folk medicine, flavorings, some TOXIC.
Unabridged references: [Cronquist & Reveal 1984 Intermountain Flora 4:308]" ^[Jepson]

Local Species;

1. Marrubium vulgare - common horehound ^[E-flora]

References

1. [E-flora] http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Marrubium%20vulgare, Accessed March 26, 2015
2. [Jepson]Marrubium, John M. Miller & Dieter H. Wilken, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=9457, accessed on Feb 19 2015
3. [PFAF]http://www.pfaf.org/user/Plant.aspx?LatinName=Marrubium+vulgare, Accessed March 26, 2015