Side Effects Use of the tea and essential oil has resulted in anaphylactic shock, contact dermatitis, and other severe allergic reactions. Persons who are allergic to asters, chrysanthemums, ragweed, and other members of the Asteraceae daisy family should avoid chamomile. Toxicities Animal fed chamomile showed few ill effects. References 1. Chamomile. Review of Natural Products. factsandcomparisons4.0 [online]. 2007. Available from Wolters Kluwer Health, Inc. Accessed April 4, 2007. Copyright © 2009 Wolters Kluwer Health Herbal Pharmacy: Chamomile This widely available herb has diverse therapeutic uses, including antiphlogistic, sedative and antimicrobial effects. George Nemecz, Ph.D. ________________________________________ Among the oldest known medicinal herbs, chamomile was used by the Egyptians to cure ague and as an offering to their gods. The aroma of the fresh flowers is similar to the scent of certain apples. The Greeks, noting this characteristic, called it kamai-melon (ground apple). The Arab herb physician Abul Abbas mentions how the use of this plant spread from the Middle East to Spain. Hippocrates described this herb as helpful in the treatment of congestion and dysmenorrhea. Dioskurides, Galen and Plinius also recommended chamomile tea for inflammation of the mouth, and a sitz bath with chamomile tea or tincture added in cases of painful menstruation.1 The essential oils of chamomile and chrysanthemum were frequently used in the treatment of malaria. Oil infusions of chamomile or the distilled essential oils are also popularly used to treat stomach ulcers, as described by Saladin in the fifteenth century. Chamomile extract, oil, tea, poultice, vapor, and ointment are folk remedies but also have been used by medical practitioners throughout history. A comprehensive list of chamomile uses would be very long, but the most common applications are for the treatment of anxiety, insomnia, vertigo, gastritis, colitis, teething, conjunctivitis, inflamed skin, bronchitis and laryngitis. There are actually two herbs commonly called chamomile: Roman (common) chamomile and German (Hungarian chamomile, wild chamomile, scented mayweed). Roman chamomile (Chamaemelum nobile, Anthemis nobilis) is native in southwestern and northwestern regions of Europe (Spain, France, England) and is scattered around the eastern Mediterranean, the Balkans and Crimea. German chamomile (Matricaria recutita, Chamomilla recutita) is originally native to southeastern and southern Europe.2 It is one of the most commonly distributed medicinal herbs all over the world, except the tropical and the arctic regions. Both chamomiles are used in traditional herbalism and medicine; however, German chamomile is more frequently preferred for medicinal use. In addition, chamomile extract and essential oils are frequently used as components in several cosmetic and hygienic products. Chamomilla recutita is an annual herb with short but widespread roots. It varies in size (from small to two feet) depending on the locality and the soil. The leaves are finely divided—the lower ones grow in threes, the middle are paired and the upper is a single pinnate. The mildly scented flowers are arranged in flower heads, which are convex when they first bloom and later become conical in shape. The head is surrounded by 12–18 tongue-shaped, white ray florets and the disk florets. The flowers are collected from May to July.2 Roman chamomile is a very aromatic perennial herb and is more robust than Chamomilla recutita. The flower heads are hemispherical and densely surrounded by silvery white florets. It is a low-growing plant—less than 10 inches in height. The hairy and branched stems are covered with leaves divided into threadlike segments. This fineness gives the whole plant a feathery appearance.3 Chemical Composition and Pharmacological Action Chamomilla recutita, the sun-loving plant of the plains, is rich in active ingredients and has remained one of the most popular herbs since ancient times. There are different classes of active constituents, which have been isolated and used individually in medical practice and cosmetics. The plant contains 0.24%–1.9% volatile oil, which is a wonderful blend of different individual oils. This oil, extracted from flower heads by steam distillation, can range in color from brilliant blue to deep green when fresh but fades over time to dark yellow. Despite fading, the oil does not lose its potency. The oil contains a-bisabolol (up to 50%) chamazulene cyclic sesquiterpenes,4-6 which directly reduce inflammation and are mild antibacterials. The essential oil also contains bisabolol oxides, farnesene and spiro-ether, which have anti-inflammatory and antispasmodic actions. The essential oil of Roman chamomile contains less chamazulene and is mainly constituted from esters of angelic acid and tiglic acid. It also contains farnesene and -pinene.4 When a mild sedative is required, Roman chamomile is preferred. Important flavonoids have been identified in German chamomile, including apigenin, luteolin and quercetin. Recent research indicates that they display more or less inhibitory effects on certain malignant cell proliferation in vitro.7 Some alkylated flavonoids, such as chrysoplenin, chrysoplenol and jaceidin, also have been traced. These compounds have recently been shown to possess anti-inflammatory and antispasmodic activity.6 Other classes of compounds identified are coumarins, herniarin and umbelliferone. These have anti-inflammatory properties.8 In addition, Matricaria recutita contains phenolic carboxylic acids such as vanillic, anisic, syringic and caffeic acids. Other relevant constituents are anthemic acid, anthemidine tannin and matricarin. Roman chamomile contains up to 0.6% of sesquiterpene lactones of the germacranolide type, mainly nobilin and 3-epinobilin. Some of the important flavonoids identified in matricaria, such as apigenin, luteolin and apiin, are also found in Roman chamomile, as is phenolic carboxylic acids (caffeic, ferulic), coumarins and thiophene derivatives.4 Medicinal and Other Uses of Chamomile Chamomile contains a wide variety of active constituents. Each expresses a specific action, but the fascinating holistic effect is a result of all of the components working together. Relatively few clinical and animal studies were carried out using whole plant extract or essential oil. In 1927, Arnold and co-workers started to study the antiphlogistic effect of chamomile. In 1933, Heuber and Graube identified a major component of chamomile oil (chamazulen) responsible for the antiphlogistic effect.1 However, recently isolated components have been researched for further information on medicinal value. Antiphlogistic Effects: The antiphlogistic action of chamomile has been recognized for many years. The standardization of the chamomile extract for main components raised questions about which has the most potent antiphlogistic effect. Experiments conducted in rat paw edema (carrageenin) showed that (–) -bisabolol has prominent antiphlogistic effects more marked than that of bisabolol oxides and the synthetic racem bisabolol. Chamazulene and guajazulene were also less effective compared to (–) -bisabolol. However, chamazulene showed almost constant effects up to four hours after administration, while quajazulene’s effect declined after two hours.9-10 The marked antiphlogistic effect of (–) -bisabolol was further substantiated in a number of different experimental models such as UV-erythema of guinea pig, yeast fever of rats and in adjuvant arthritis of rats.9 Oxygen free radical-related reactions are implicated in numerous pathophysiological conditions such as inflammation, gastric ulceration, neuronal degeneration and tumor promotion. Chamazulene was found to produce a significant protection against lipid peroxidation induced by Fe2+/ascorbate.11 Active oxygen species attacking membrane lipids (mainly polyunsaturated fatty acids) generate inflammatory responses and tissue damage. Therefore, chamazulene as a potent antioxidant with low IC50 (18 �M) is comparable to known antioxidants such as quercetin (IC50 17 �M) or propyl gallate (IC50 10 �M), which have therapeutic value in the anti-inflammatory processes.11 Oxygen free radicals are also essential for the activation of 5-lipoxygenase enzyme, a key enzyme in leukotriene production. Since leukotrienes are involved in the initiation and maintenance of a variety of inflammatory diseases, it was reasonable to test the effect of chamazulene on leukotriene synthesis. Indeed, chamazulene inhibited the formation of leukotriene B4 in rat peritoneal neutrophilic granulocytes, in a concentration-dependent manner.12 Chamazulene, an active ingredient of chamomile, is a potent antioxidant valuable in the anti-inflammatory process. (–) -bisabolol was studied in experimental ulcer models with rats.13 One of the following were used to induce ulcers: 20 mg/kg indomethacin, 3.5 mL 50% ethanol, 0.05 mL 80% acetic acid, or stress produced by periodic noise. (–) -bisabolol inhibited occurrence of ulcers induced by indomethacin, stress or ethanol and shortened healing time of acetic acid-induced ulcers.13 The influence of chamazulene, a-bisabolol and one of the dicycloethers (components of essential oil) was studied on protamine sulfate-provoked degranulation of mast cells from Lewis-1a rats. The degranulation effect was determined by measuring histamine liberation. Chamazulene and -bisabolol had no distinct inhibition but dicycloether above 10-4 M inhibited degranulation.14 Spasmolytic Effect: A systematic comparison of spasmolytic action of the hydrophilic and lipophilic compounds of chamomile was carried out on isolated guinea pig ileum.15 Series of tests showed that the total extract and some of the ingredients had a dose-dependent spasmolytic effect on the smooth muscles of the intestine. The lipophilic (-) -bisabolol, bisabolol oxides showed a marked papaverine-like musculotropically spasmolytic action while the essential oil had the least effect. The chamomile flavones apigenin, luteolin patuletin and quercetin were also very active in their spasmolytic action. These studies showed that the lipophilic as well as the hydrophilic components take part in the therapeutic action.15 Sedative, Hypnotic, Analgesic Effects: Chamomile tea is known for its sedative and hypnotic effects. In a psychological study, images were used to induce slight negative and positive moods in 22 subjects. Subjects visualized 20 positive and 20 negative scenes while under the influence of either chamomile oil or a placebo. Chamomile oil significantly increased the latency of all images and shifted the mood ratings and frequency judgments in a positive direction.16 The development of depression and anxiety is frequent in menopausal women. In an experimental model, inhalation of chamomile oil vapor reduced restriction stress-induced elevation of plasma ACTH level in ovariectomized rats.17 One mg/kg oral diazepam also effectively decreased the stress-induced ACTH level. Combined application of diazepam and chamomile oil vapor further decreased the stress-related elevation of ACTH. The authors suggested that chamomile oil might affect the GABAergic system in the rat brain, similarly as the benzodiazepine agonist.17 The anxiolytic effect of apigenin was tested in mice.18 Apigenin, isolated from the aqueous extract of Matricaria recutita, had a clear anxiolytic activity in mice, as tested in the elevated plus-maze. A dosage up to 10 mg/kg produced no sedation or muscle relaxant effect. However, a 10-fold increase in dosage produced a mild sedative effect. Binding studies of apigenin on synaptosomal membrane, prepared from bovine cerebral cortex, showed significant affinity for the central benzodiazepine receptor. Apigenin competitively inhibited the binding of flunitrazepam, a benzodiazepine receptor ligand, with a Ki of 4 �M, and had no effect on muscarinic receptor, 1-adrenoceptors and on the binding of muscimol to GABAA receptors.18 The authors concluded that apigenin is a ligand for the benzodiazepine receptors, exerting anxiolytic and slight sedative effects but not being anticonvulsant or myorelaxant. The effect of chamomile tea on the cardiovascular system is unclear. Twelve patients with cardiac disease underwent cardiac catheterization. Hemodynamic data obtained prior to and 30 min. after ingestion of chamomile tea demonstrated a small but statistically significant (p < 0.05) increase in the mean brachial artery pressure. No other significant hemodynamic changes were observed.19 However, 10 of 12 patients fell into deep sleep shortly after drinking the tea. Antimicrobial Activity of Essential Oil: The volatile oil prepared from flower heads (fresh or dried) by steam distillation has been tested against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (E. coli, Pseudomonas aeruginosa) as well as a fungus, Candida albicans. Oil concentrations above 0.05% were very effective against the Gram-positive bacteria and Candida. The Gram-negative bacteria were relatively less sensitive20 except for Bacillus subtilis.21 The antibacterial effect may depend on the concentration of chamazulen, bisabolol and bisabolol oxides in the extract. Even at low concentrations,
Posted on: Fri, 24 Oct 2014 10:52:29 +0000
Trending Topics
Recently Viewed Topics
© 2015