Significant carminative herbs Peppermint

Although many plant materials contain volatile oils and therefore possess some carminative properties, one of the most effective and widely used is certainly peppermint. Consisting of the leaves and flowering tops of Mentha x piperita L. (family Lamiaceae), this herb is officially listed in the NF XVII. It contains 0.5–4 percent (average of about 1.5 percent) of a volatile oil composed of 50–78 percent free (*)-menthol and from 5 to 20 percent menthol combined in various esters such as the acetate or isoval- erate. It also contains (+)- and (*)-menthone, (+)-isomenthone, (+)-neomen-

thone, (+)-menthofuran, and eucalyptol, as well as other monoterpenes. 61 Although flavonoid pigments found in the leaf may also exert some physi- ological effects, 62 there is little question that most of the activity is due to the constituents of the oil, primarily menthol. Peppermint oil has long been an extremely popular flavoring agent in products ranging from chewing gum to after-dinner mints. It is probably the most widely used carminative, acting in the broad sense defined by

Schilcher. 57 The German Commission E has found peppermint or its volatile oil to be effective as a spasmolytic (particularly for discomfort caused by spasms in the upper digestive tract), a stimulant of the flow of bile, an

antibacterial, and a promoter of gastric secretions. 63 On the other hand, in 1990, the U.S. Food and Drug Administration declared peppermint oil to

be ineffective as a digestive aid and banned its use as a nonprescription drug for this purpose. 64 What this actually means is that the FDA was not presented with evidence proving the efficacy of peppermint as a digestive aid. As previously explained, this would not be financially feasible in the United States. It does not mean that peppermint oil is an ineffective aid to digestion.

One of the most frequent diagnoses made for patients because of gastrointestinal complaints is non-ulcer dyspepsia. It is characterized by motility disturbances with bloated abdomen, a feeling of fullness, diffuse pain, nausea, vomiting, and intolerance of foodstuffs. The efficacy and safety of the herbal combination of peppermint oil (90 mg) and caraway oil (50 mg) in an enteric-coated capsule have been studied in a double- blind, placebo-controlled multicenter trial in patients with non-ulcer dyspepsia. After four weeks of treatment, the group of patients treated

Chapter three: Digestive system problems

41 with the herbal combination had improved significantly with few adverse

effects. 65 Peppermint oil is also used to relieve the symptoms of irrita- ble bowel syndrome, and experimental evidence indicates that it acts by relaxing intestinal smooth muscle by reducing calcium availability in the muscle membrane. 66

Peppermint is GRAS listed, and both it and peppermint oil are rec- ognized as flavoring agents in the NF XVII. Peppermint tea is prepared by pouring about 2/3 cup of boiling water over a tablespoonful of the recently dried leaves and steeping for five to ten minutes. Drink this amount of tea three to four times daily between meals to relieve upset stomach. Peppermint spirit (USP XXII), an alcoholic solution containing 10 percent peppermint oil and 1 percent peppermint leaf extract, is also available in pharmacies. The usual dose is 1 mL (20 drops) taken with water.

Regular consumption of peppermint tea is considered safe for normal persons, although excessive use of the volatile oil (0.3 g = 12 drops) may produce some toxic effects. 67 Allergic reactions to menthol have also been reported. 67–69 Peppermint tea should not be given to infants or very small children because they often experience an unpleasant choking sensation due to the menthol. 70

Chamomile Another extremely popular herb for the treatment of indigestion, as well as various other conditions, is chamomile. German or Hungarian chamomile, often referred to as true chamomile or matricaria, con- sists of the dried flower heads of a plant now technically designated Matricaria recutita L. In the older literature on medicinal plants, it is usu-

ally referred to as Matricaria chamomilla L.p.p. or as Chamomilla recutita (L.) Rauschert. At least seven other scientific names have been used to designate the plant. A member of the daisy family and formerly known as the Compositae, it is now called the Asteraceae by most taxonomists. The important thing to remember when attempting to maneuver through this nomenclatural maze of five English common names, ten scientific names, and two plant family designations is that all of the names refer to a single species of plant. Its popularity as a traditional medicine is so great that in Germany it was declared the medicinal plant of the year for 1987. 71

A related plant is Roman or English chamomile, composed of the flower heads of Chamaemelum nobile (L.) All. syn. Anthemis nobilis L. (family Asteraceae). Its constituents are not identical to those of German chamomile, but both plants are similarly employed. In Great Britain, Roman chamomile is the herb of choice; on the Continent, German chamomile is preferred. The latter is also the species most commonly consumed in the United States.

42 Tyler's herbs of choice: The therapeutic use of phytomedicinals The literature on the chamomiles is extensive. Die Kamille, a 152-page

book by H. Schilcher, provides comprehensive coverage. 72 Mann and Staba’s 1986 review is the most recent one in the English language. 73 It provides 220 references to various agronomic, botanical, chemical, and pharmacological aspects of the herbs.

A blue-colored volatile oil is obtained from the chamomiles by steam distillation in yields up to nearly 2 percent. The blue color is due to chamazulene, which is formed during distillation from matricin, a sesquiterpene found in chamomile flowers. Chamazulene was shown to have anti-inflammatory action as early as the 1930s. Its precursor, matricin, is also an active anti-inflammatory. In the 1950s, it was found that the constituent flavonoids, especially apigenin, have both anti-inflammatory and antispasmodic activities. Later it was shown that the terpenoids

(–)- α-bisabolol and (–)-α-bisabololoxides A and B have similar activities. 74 Della Loggia and others, in 1990, determined that topically the most active anti-inflammatory principle in chamomile is apigenin, followed by matir-

icn, (–)- α-bisabolol, and chamazulene, with respective ID 25 values of 12, 79, 105, and 1,080 µg/cm 2 . 75 Chamazulene and bisabolol are very unstable and are best preserved in an alcoholic tincture; the essential oil exhibited the weakest inhibition of edema, and an alcoholic extract was far superior.

The chamomiles are used internally for digestive disturbances. Like peppermint, they possess carminative (antispasmodic) effects; however, unlike peppermint, they exert a pronounced anti-inflammatory activity on the gastrointestinal tract. In the United States, chamomile tea is most widely used for this purpose. It is prepared by pouring boiling water over

a heaping tablespoonful (about 3 g) of the flower heads and allowing them to steep in a covered vessel for ten to fifteen minutes. A cup of freshly prepared tea is drunk between meals three or four times daily for stomach or intestinal disturbances. As previously noted, only a small fraction of the volatile oil (roughly 10 percent) and about 30 percent of the flavonoids are extracted in this way, but there is reason to believe the tea provides a cumulative beneficial effect.

Both German and Roman chamomile are considered safe for normal human consumption and are GRAS listed by the FDA. Some aller- gies have been reported, however, so persons with known sensitivities to them or to various other members of the Asteraceae (e.g., ragweed, asters, chrysanthemums) should be cautious about consuming chamomile teas. However, this rather remote possibility may have been greatly overem-

phasized in some of the nonmedical literature. 76 Only five cases of allergy specifically attributed to German chamomile were identified worldwide between 1887 and 1982. 77 However, a recent report indicates that a German chamomile ether extract used in allergic patch testing from 1985 to 1990 in 3,851 tested individuals produced an allergic reaction in sixty-six patients, or 1.7 percent. 78

Chapter three: Digestive system problems

43 Most of the other forty-plus reports of allergic reaction probably

relate to the common adulterant/substitute Anthemis cotula L. (stinking mayweed, dog’s chamomile, dog fennel), which contains the particularly

noxious sesquiterpene, anthecotulid. 79 In an alarming case of professional botanical misidentification, botanists at the University of Texas, Austin, vouchered a plant as M. chamomilla of Argentinean origin containing 7.3 percent anthecotulid, which was subsequently determined to be A. cot-

ula. 77 The German Commission E considers German chamomile effective internally for gastrointestinal (GI) spasm and inflammatory conditions of the GI tract. It was also found to be effective when used as a mouthwash for irritations and minor infections of the mouth and gums.

In Europe today, a large number of pharmaceutical preparations are available containing either extracts of chamomile or chamomile volatile oil. Some are creams or lotions intended to treat various skin irritations, includ- ing those caused by bacterial infections. Other forms are suitable for inhala- tion and are designed to relieve bronchial irritation; still others are used as baths or rinses to alleviate irritations in the anogenital regions. Commission

E has concluded that German chamomile is also effective for these pur- poses. 80 However, because none of these preparations has been approved for use as an OTC drug in the United States and such dosage forms are not ordi- narily available there, their therapeutic use will not be discussed further.

Finally, it should be noted that chamomile herb is not inexpensive and is relatively easy to adulterate. To ensure quality, purchase it only in the form of the whole flower heads, which are easy to identify with a little experience, and make certain that no appreciable quantity of stems is present (less than 10 percent). It is best to avoid pulverized or powdered chamomile, the quality of which is difficult to determine, even by experts. Any preparations containing chamomile oil (most will be foreign made) should be acquired only from firms having outstanding reputations for quality products. Three-quarters of the commercial chamomile oil sam- ples examined in 1987 were found to be adulterated, often with cheaper, synthetically prepared, blue-colored compounds such as guaiazulene. 81

A natural source of chamazulene is the cheaper essential oil of yarrow (Achillea millefolium L.) and the wood of the Brazilian tree Vanillosmopsis erythropappa Schultz Bip., which yields up to 3 percent essential oil consisting almost exclusively of (–)- α-bisabolol, which has been used as a cheaper source of that terpenoid. Chamazulene from A. millefolium and bisabolol from V. erythropappa can only be distinguished from their corresponding chamomile constituents by isotope ratio mass spectrometry. 82

Significant carminative herbs Peppermint