Tuesday, May 30, 2006


The chamomiles (or camomiles) have long been used and cultivated by Europeans and Americans. There is hardly one western herbal published in the past 500 years that does not include this group of plants. Tyler (1993) notes that the Germans refer to it as alles zutraut (capable of anything), equating its reputation (though not uses) as a popular European herb with the status afforded ginseng in other cultures.

The word chamomile is derived from the Greek chamos (ground) and melos (apple), referring to the plant's low growing habit and the fact that the fresh blooms are somewhat apple-scented (Smith, 1963).
According to Hill (1948), accurate identity of a plant under discussion as "chamomile" is hampered by the fact that the name has been applied to a dozen or more species in six genera of the aster family (Asteraceae or Compositae). However, of all these plants, only two species are generally utilized in the herb trade and in broad historical folk usage.
Unfortunately for the botanist and lay person alike, both of those species have, in the past 20 years, been referred to by as many as five different Latin species names, as well as a number of common names. Tucker (1986; Tucker et al., 1987, 1989) retains Chamomilla recutita (L.) Rauschert as the proper botanical name of the "common chamomile" of the European continent, better known as Hungarian or German chamomile, also known by the synonyms Matricaria chamomilla and M. recutita. Tucker and co-workers cite Kay et al. (1976) as the authority. However, Jeffery (1979) provides convincing evidence for relegating the genus name Chamomilla to synonymy with Matricaria. Conveniently, Matricaria recutita is the name cited in Hortus Third (Liberty Hyde Bailey Hortorium,- 1976). This book has been widely used as a source of botanical names by the American herb trade. The unfortunate part of this taxonomic shuffling is that the lay person, herb trader, or research scientist must source information on the plant under at least three different Latin names, depending upon the year of publication. Such a complex problem for a simple herb! Henceforth, we will deem the major source plant of the chamomile of commerce Matricaria recutital "German chamomile," at least until a taxonomist provides a more definitive interpretation of the nomenclature.
Let's turn to the "common chamomile" of England, better known as English or Roman chamomile. In many herb books published prior to 1976, this plant is called Anthemis nobilis L. However, in 1785, an Italian botanist, Carlo Allioni (1728-1804), placed this plant in the genus Chamaemelum, naming it Chamaemelum nobile (L.) All. Buried in obscurity for nearly 200 years, the name resurfaced in the mid-1970s and was adopted in volume 4 of Flora Europaea, as well as Hortus Third. It is again retained by Tucker (1986; Tucker etal., 1987,1989). Chamaemelum nobile is best known as Roman chamomile, the name by which we will refer to it here. The name Roman chamomile was first bestowed upon the plant by Joachim Camerarius in 1598, after observing it growing abundantly in the vicinity of Rome (Fluckiger and Hanbury, 1879).
German chamomile is a sweet-scented, smooth, branched annual growing to 2 1/2 ft. in height. It is native to Europe and Western Asia, and has become widely naturalized in the U.S. (L. H. Bailey Hortorium, 1976).
Roman chamomile is an aromatic, creeping perennial, growing to one foot in height. It hails from the United Kingdom (UK) and is widely grown in American herb gardens.
Historically, Roman and German chamomiles have been used interchangeably or confused. The German is preferred on the European continent, while the Roman chamomile has been more widely used in the U.K. In the U.S., German chamomile is by far the most widely consumed of the two species. Despite the fact that the two plants have often been lumped together as "chamomiles," their chemical components and essential oils are quite different, and each should be treated as a separate entity (Mann and Staba, 1986). In addition to genetic differences, quality and quantity of essential oil and other plant components, as in most medicinal plants, are dependent upon a wide range of variables such as environmental factors, cultivation practices, plant part, plant age, and postharvest handling. Articles relative to these subjects are cited by Mann and Staba, (1986) and Simon, Chadwick, and Craker (1984).
German chamomile has a long tradition as a folk or domestic remedy used for a wide variety of purposes including an external compress or fomentation for sciatica, gout, lumbago, inflammations, rheumatism, and skin ailments. A tea (infusion), decoction, or tincture has long been used for treating colic, convulsions, croup, diarrhea, fever, indigestion, insomnia, infantile convulsions, toothache, bleeding or swollen gums, a folk cancer remedy, and many other uses. Historically, Roman chamomile has been utilized for similar purposes. It is best known as a pleasant-tasting, or healthful beverage tea (Leung & Foster, 1996; Duke, 1985).
In the late 1970s and the 1980s several popular and scientific articles strongly warned against drinking chamomile tea, the warning based on an isolated report of anaphylactic reaction resulting from drinking chamomile tea (Casterline, 1980; Benner and Lee, 1973). One report (Hausen, 1979) tested 25 human subjects known or thought to be allergic to aster family members, and found that two of the patients (8 percent) were allergic to chamomile. Cross-reactions with other aster family members were also observed.
Mann and Staba (1986) suggest that a possible source of allergic reactions attributed to chamomile flowers may be other closely related, more allergenic plants, such as Anthemis cotula, dog fennel or mayweed, which is known to cause toxic or irritating reactions, and is sometimes offered as or may be an adulterant to chamomile. These authors suggest proper identification and purity of chamomiles as a preventative measure, but warn that those with known sensitivities to aster family members (including ragweed, asters, chrysanthemums, etc.) may best be advised to avoid German and Roman chamomiles and their products.
In the proposed European monograph on chamomile flowers produced by ESCOP (European Scientific Cooperative for Phytotherapy) there are several headings that address issues relative to potential side effects or adverse reactions. These include headings for contraindications, side effects, use during pregnancy and lactation, special warnings, interactions, duration of administration, and overdose. Under contraindications, we find "none known." Use during pregnancy and lactation? "No adverse effects reported." Special warnings? "None required." Interactions? "None reported." Duration of administration? "No restriction." Overdose? "No intoxication symptoms reported." The side effect heading in the ESCOP monograph reads, "Extremely rare contact allergy" (ESCOP, 1990). What is rare? Tyler (1993), while reiterating a word of caution for those who suffer from hypersensitivity to ragweeds and other aster family members, notes that normal persons should not be deterred from consuming the herb. He cites a survey of world literature (Hausen, Busker, and Carle, 1984) which found only about 50 reports of chamomile allergies reported between 1887 and 1982. Only five of these reports were attributed to the widely available German chamomile (Matricaria recutita). The vast majority involved the genus Anthemis, primarily Anthemis cotula, which is not in commerce. These reports, however, emphasized the need for proper identification of source plants used in herbal preparations. The Commission E, an expert panel of the German Institute for Drugs and Medical Devices, concurs that there is no known adverse reactions nor contraindications for the nonprescription drug use of German chamomile (Blumenthal, et al., 1996).
Contemporary Medicinal Use
Azulenes, a group of chemical components found in both species of chamomile, possess experimental antiallergenic activity (Farnsworth and Morgan, 1972; Mann and Staba, 1986). Both histamine release and inhibition of histamine discharge have been advanced as mechanisms for the potential antiallergenic action of azulenes. Mann and Staba (1986) suggest that, since azulenes seem to prevent allergenic seizure, inhibition of histamine is probably involved in the true mechanism of their action.
In modem Europe, chamomile products, including extracts, tinctures, tisanes (teas), and salves, are widely used as anti-inflammatory, antibacterial, antispasmodic, and sedative agents. Extracts are used to allay pain and irritation, clean wounds and ulcers, and aid prevention and therapy of irradiated skin injuries, as well as treat cystitis and dental afflictions (Mann and Staba, 1986). The plant is included in the pharmacopeias of 26 countries (Salamon, 1992).
The German Commission E approves German chamomile preparations for external use in cases of inflammations of skin and mucous membranes, bacterial skin diseases, diseases of mouth and gums, inflammation and irritation of the upper respiratory tract, and inflammations of the ano-genital area by using chamomile baths. Internally, chamomile is approved for gastrointestinal spasms and inflammatory diseases of the gastrointestinal tract. The flowers must have a minimum of four percent essential oil (Blumenthal, et al., 1996).
Extracts and a number of components of chamomile, including azulenes (chamazulene) and alpha-bisabolol, have been shown to have anti-inflammatory activity. Chamazulene, comprising 5 percent of the essential oil, is an artifactual component formed during heating of teas and extracts (Der Marderosian and Liberti, 1988). This activity has been demonstrated, not only by long empirical use, but by a number of different laboratory models as well. Studies also show that alpha-bisabolol has a protective effect against peptic ulcers, as well as antibacterial and antifungal activity. Alpha-bisabolol has also been shown to reduce fever and shorten the healing time of skin burns in laboratory animals (Der Marderosian and Liberti, 1988). These two compounds are considered primary active components in German chamomile. Many commercial German chamomile preparations are standardized to chamazulene and alpha-bisabolol content (Tyler, 1993; Mann and Staba, 1986).
Four basic chemical types of Matricaria recutita (A, B, C, and D) are now recognized according to qualitative and quantitative analysis of the essential oil. Consequently, in the major chamomile production countries (Argentina, Czech Republic, Germany, Hungary, Poland, and Slovakia), intensive plant improvement programs have been initiated to produce plants with high levels of defined chemical components (Salamon, 1992).
About 120 secondary metabolite chemical constituents have been identified in chamomile, including 28 terpenoids, 36 flavonoids, and 52 additional compounds, all with potential pharmacological activity (Salamon, 1992). Components in the essential oil of German chamomile contribute to its smooth muscle relaxing activity. Nonvolatile constituents, including flavones (apigenin, luteolin, patuletin, and quercetin) are also antispasmodic (Tyler, 1993). Chamomile teas absorb only about 10-15 percent of the essential oil available in the flowers, but, if used over a long period of time, have the potential for a cumulative therapeutic effect (Der Marderosian and Liberti, 1988; Farnsworth and Morgan, 1972).
Chamomiles have been used for centuries in teas as a mild, relaxing sleep aid, treatment for fevers, colds, stomach ailments, and as an anti-inflammatory, to name only a few therapeutic uses. Extensive scientific research over the past 20 years has confirmed many of the traditional uses for the plant and established pharmacological mechanisms for the plant's therapeutic activity, including antipeptic, antispasmodic, antipyretic, antibacterial, antifungal, and antiallergenic activity. In addition to medicinal use, chamomiles enjoy wide usage, especially in Europe, Latin America, and the U.S., as a refreshing beverage tea and as an ingredient in numerous cosmetic and external preparations. One source estimates that over one million cups of chamomile tea are ingested worldwide each day (McCaleb, 1990).
Reference Source: Herbal gram.org

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