Antitussive herbs

Many antitussive herbs are claimed also to have anti-inflammatory, antioxidant, or antiallergic properties, or a combination, usually on the basis of in vitro studies. Presumably they would be especially effective against coughs due to URTI such... 

We have selected four herbs which seem to provide the most evidence for their antitussive effectiveness and mechanisms. Table 1 lists a further 13 antitussive herbs with some published evidence as to their effectiveness and modes of action. Very many more herbs, with virtually no good evidence for their efficacy, are listed elsewhere (Blumenthal 2000 Skidmore-Roth 2001 Fetrow and Avila 2001 Ziment 2001, 2002). 

It is medicinally used from Korea to Cambodia, Laos, and Vietnam. In Korea, the plant is used as an aphrodisiac for males and the elderly. In Japan, a decoction of the root is drunk to treat cough, invigorate, and treat tuberculosis. In Taiwan, the plant is an external remedy for snake bites. In Cambodia, Laos, and Vietnam, the roots are used to treat bronchitis, amnesia, and to stimulate memory and urination. The antitussive property is very probably owed to polygalasaponins, which are known to abound in the plant (24-26). It would be interesting to know whether the tonic properties mentioned here are owed to serotoninergic mechanisms. What is the alkaloidal content of this herb ... 

Aristolochia contorta Bunge. A. kaempferi Willd. A. longa Thunb. A. recurvilabra Hance Ma Dou Ling (stem) Aristolochic acid A, aristolochic acid D, aristoloside, magnoflorine, oleanolic acid, beta-sitosterol, hederagenin.48 This herb is toxic. Treat pulmonary disorders, antitussive, an expectorant in asthma and bronchitis. 

Liriope graminifolia Bak. L. platyphylla Wang Tang L. spicata Lour. Mai Men Dong (root) Mucilage.49 This herb is used to produce Ophiopogon.60 Antitussive, expectorant, emollient. 

Nandina domestica Thunb. Nan Tian Zhu (Sacred bamboo) (fruit, bark, leaf) Domesticine, nandinine, cyanic acid, nandazurine, berberine.49 This herb is toxic. Antitussive. 

Phytolacca acinosa Roxb. P. americana L. P japonica Makino P. kaempferi A. Gray P octandra Bge. P. pekinensis Hance Shang Lu (Pokeberry) (root) Phytolacine, phytolaccatoxin, oxyristic acid, jaligonic acid, saponins.33-144 This herb is toxic. Antitussive, diuretic, antibacterial, antiinflammatory. 

Pinellia temata (Thunb.) Breit. P. tuberifera Tenore Ban Xia (tuber) 1-ephedrine, choline, amino acids.33-144 This herb is toxic. Antiemetic, antitussive and antidote for strychnine intoxication. 

Trichosanth.es kirilowii Maxim. T. uniflora Hao Gua Lou, Tian Hua Fen (Chinese snakegourd) (root, seed) Trichosanthin, polysaccharides, saponin, organic acids, resin, protein (TAP29).33 261 This herb is highly toxic. Treat pectoris and acute mastitis. Antitussive, as an expectorant, anti-HIV activity. 

Herbs for activating blood circulation and removing blood stasis Expectorants, antitussives, and dyspnea-relieving herbs Sedatives... 

It has traditionally been a primary herb of choice for treating colds and flu. It is especially useful for children in that it is safe in large quantities and yet tastes quite good. A relatively unknown fact is that ginger s antitussive (anticough) action rivals that of codeine, and its strong expectorant and antihistamine actions help thin bronchial mucus and move it up and out of the system. This makes it a perfect herb for upper... 

Many herbal remedies that may be antitussive could act indirectly on cough for example, by expectorant, demulcent, bronchodUator, or local anesthetic actions. Ziment (2002) lists 15 such indirect ways in which herbal antitussives may work (see also later) and lists over 120 herbs which are claimed, nearly always with little or no evidence, to act via these indirect mechanisms. With the exception of bronchodilation, there are no effective means of assessing these indirect actions, and the relationship between bronchodilation and cough is little understood. 

Analysis of a number of herbal extracts has identified chemicals later shown to have true antitussive actions in experimental animals and sometimes in humans. To conclude that the herb itself is a remedy for cough is clearly unjustifiable on fhis evidence, allhough if is a reasonable hypothesis that could be tested. To give an example, pure opioids such as morphine extracted from poppy (Papiver somniferum) are established antimssives in animals and humans, but there seems to be no evidence that nonpurified extracts of the plant, as would be used in herbal medicine, are also effective if they were, they could be working by a placebo effect. 

Some herbal treatments for cough contain local anesthetics that might act on nervous sensors in the mucosa of the pharynx and larynx before the medicine reaches the stomach. These include Erythroxylum coca (cocaine). Cannabis sativa (marijuana), and possibly Syzygium aromaticum (clove oil). However, there seems to be no evidence that these herbs have antitussive actions by this mechanism. Most local anesthetics also taste bitter, which could also have an antitussive action (see later). 

Herbs claimed or shown to have antispasmodic effects, in vitro and/or in vivo, and to be antitussive, include Adhartoda vasica (malibar nut), Petasites hybridus (butterbur). Ephedra sinica (ephedra), Mentha peperita (peppermint), Atropa species (atropine). Curcuma longa (turmeric), Ocimum sanctum (basil), and Piper longum (pepper). 

In this section we select, inevitably rather arbiharily, four herbal cough treatments for which the effectiveness and mechanisms have been studied. With many other herbs there are a few pointers in the literature that the herb may be objectively considered an effective antitussive in humans, but the evidence is so thin as to be unconvincing (Table 1). In some instances, research only on animals or animal preparations has been done. 

Nosalova G, Strapkova A, Korpas J et al (1989) Objective assessment of cough suppressants under normal and experimental conditions. Drugs Exp Chn Res 15 77-81 Nosalova G, Kardosova A, Franova S (2000) Antitussive activity of a glucuronoxylan from Rud-beckiafukgida compared to the potency of two polysaccharide complexes from the same herb, Pharmazie 55 65-68... 

Laminaria possesses remarkable properties that make it a wonderful component of dietary supplements. Due to its amazing medicinal benefits, it has been used in traditional Chinese medicine since centuries and is listed in the Chinese pharmacopeia. In general. Laminaria is considered as a cold, salty herb, prescribed to cleanse heat, resolve phlegm, and soften and disperse hard accumulations (e.g., goiters). It is often used to control edema, as an expectorant and antitussive, and as a remedy for testicular pain and swelling. Despite its salty character, the herb is slightly hypotensive. 

Panax japonicus var. major is a wild dicotyledonous herb of Araliaceae which is maiidy distributed in southwest China and Himalayas areas . Its root has been used as an expectorant, antitussive and hemostatic in Chinese herbal medicine for a long time. And the main active constituents were thought as a wide range of saponins and sapogenins . Biotechnological alternative, i.e. cullus cultures, cell suspension cultures and hairy root cultures, has been adopted for in vitro saponin production. But, no study has been made for the tissue culture and secondary metabolism of this plant. This paper describes the hairy root culture and its saponin formation. 

Fritillaria verticillata var. thunhergii (Liliaceae) is a perennial herb that grows wild in the People s Republic of China. The plant is cultivated in Japan mainly as an ornamental. The dried bulbs are known as baimo in Kampo medicine and are used as an antitussive, as an expectorant, for hemostasis and lactogenesis, and as an antipyretic. 

Traditional Medicine. Dried inflorescence and whole herb are used in both Eastern and Western cultures as diuretic, sedative, and antitussive and in treating whooping cough, asthma, bronchitis, eczema, psoriasis, and burns, among others, usually in the form of a tea, infusion, or salve (barnes duke 1) flowers used in the form of a cold tea by Iroquois women for the change of life (moerman). The whole plant or its various parts (leaves, flowers, roots, etc.) have also been extensively used in treating cancers. ... 

In Chinese medicine related Lobelia species (e.g., L. chinensis Lour, and L. sessilifolia Lamb.) are also used, the former primarily for jaundice and sores, wounds, ringworm, snakebite and insect bites, and malaria while the latter is used as an expectorant and antitussive and in treating bronchitis, ulcerous sores, snakebites, and insect and dog bites. Both herbs also contain lobeline and related alkaloids. 

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