Goldenseal (Hydrastis canadensis) is one of the most popular herbs on the U.S. market. Although a scientific basis for its use has not been established, it has been one of the herbal stars of American folk medicine for more than 200 years.
This small, herbaceous plant of the buttercup family (Ranunculaceae) has hairy, lobed leaves and bright yellow rhizomes and roots. Inconspicuous white flowers in April and May are followed by showy, bright red fruits suggestive of raspberries. Goldenseal grows in rich, moist woods, especially under beech trees, from Vermont to Minnesota and south to Georgia, Alabama, and Arkansas.
The name goldenseal comes to us from Samuel Thomson (1769-1841), the founder of a system of herbal medicine that attracted millions of followers during the first half of the nineteenth century. Thomson noted the small cuplike scars on the upper side of the rhizome and thought that they looked like wax letter seals.
Goldenseal’s primary historical use has been as a tonic for mucous membranes, particularly those of the digestive tract. White settlers learned this use from Native Americans. The Cherokee also used the roots as a wash for local inflammations and drank a decoction to treat general debility, dyspepsia, and poor appetite. The Iroquois used a decoction to treat diarrhea, liver disease, fever, sour stomach, flatulence, and pneumonia. It was an ingredient of digestive bitter tonics, the nineteenth-century counterpart to antacids. Both Native Americans and whites obtained a bright yellow dye from the rhizomes and roots.
During the past two decades, goldenseal has been one of the top-selling herbs in health-food stores, used as an antiseptic, cold remedy, substitute for antibiotics, homeostatic, diuretic, tonic, and anti-inflammatory. And let’s not omit hemorrhoids, excessive menstrual bleeding, nasal congestion, mouth and gum sores, eye afflictions, and (externally) wounds, sores, acne, and ringworm, among other ailments. Name a condition, and you can probably find a reference somewhere to goldenseal’s use for it.
Despite two centuries of use, goldenseal is still considered a folk medicine. Scientists have paid it little attention. The most recent pharmacological study on goldenseal and its constituents dates to 1950, and its author noted that there had been little research during the previous forty years. Because test conditions of early studies were not rigorous by today’s standards, the results of those studies are open to question.
Goldenseal’s pharmacological action has been attributed primarily to the alkaloids hydrastine (1.5 to 4 percent of the dried root) and berberine (1.7 to 4.5 percent of the dried root). The latter, which gives the root its bright yellow color and bitter taste, is also found in barberries, Oregon grape, and goldthread, all of which also have bright yellow roots. Other components found in goldenseal root include the alkaloids canadine, canadaline, hydrastidine, isohydrastidine, and berberastine, along with chlorogenic acid, resins, starch, and sugars.
Hydrastine is a vasoconstrictor. Berberine and hydrastine both are slightly sedative and strongly antibacterial; both stimulate the flow of bile and reduce muscle spasms. Most pharmacological studies of berberine, however, have extracted the compound from Asian species of goldthread or barberry rather than goldenseal.
One recent folk application for goldenseal sounds like something out of fiction, which in fact it was. In Stringtown on the Pike, the most popular of eight novels by the pharmacist John Uri Lloyd (1849-1936), goldenseal bitters are erroneously identified as strychnine in a chemical test by an expert in a murder trial. The accused is convicted on this testimony, although the stomach of the deceased actually contained no strychnine at all, only goldenseal, which the victim habitually drank as a digestive aid. Since the novel’s publication in 1900, the story has become a part of folklore associated with chemical-test errors. Goldenseal has been used (without success) on numerous occasions to mask the use of morphine in racehorses, and people have taken it in the hope of disguising the presence of illegal drugs in their urine. Actually, goldenseal may just as likely produce a false positive reading as a false negative; however, because of the practice of ingesting goldenseal to affect the outcome of drug testing, some labs now also test for the presence of goldenseal in a urinalysis.
The future of goldenseal in the marketplace will depend on developing cultivated supplies of the root. This relatively uncommon woodland plant, which has traditionally been wild-harvested, is becoming increasingly scarce. Although ginseng growers in the northern United States, Ontario, and British Columbia are beginning to cultivate goldenseal as well, prices have risen sharply as stands of wild goldenseal are depleted. Wholesale prices now exceed $30 per pound–more than three times those of only a few years ago.
Much more research is needed on goldenseal: on the plant itself, on substantiation of its alleged therapeutic effects, and on developing cultivated sources to meet the demand that will surely continue to climb.
The goldenseal supply problem–characterized by periodic shortages, price hikes, and concern over future supplies–is not easily defined. Over the years, a number of botanists have observed that because of overharvesting of the root, goldenseal is increasingly rare in areas where it once flourished.
More than 100 years ago, in Drugs and Medicines of North America (1884-1885), pharmacist John Uri Lloyd and his brother, botanist Curtis Gates Lloyd, recorded dramatic declines in wild populations of goldenseal, which they attributed not only to harvest of the root for medicinal markets, but also to habitat loss due to deforestation. The Lloyds painted a complex picture of economic and social reasons for periodic shortages, noting that decreases in areas or populations of goldenseal were not necessarily accompanied by decreased supplies. Historically, farm laborers and poor people collected the roots during times of economic hardship or during years of crop failure; conversely, fewer people collected goldenseal (and other herbs) during periods of economic prosperity or abundant crops. Sometimes, the entire supply of goldenseal would be consumed in one season, resulting in shortages and price increases, but this would stimulate a larger harvest the following season, causing subsequent market gluts and price decreases that discouraged harvesting the root the next year. As collectors turned their attention to other pursuits, the price of goldenseal would stabilize as stocks were exhausted, and so, as the Lloyds put it, “history repeats itself”. Recent supply shortages and high prices appear to follow the same pattern of a century ago.
The actual number of pounds harvested and consumed annually is not known. Possible reasons for the recent shortages include harvesters’ shifting to higher-priced herbs such as ginseng, periods of drought in the Southeast that have made digging the roots difficult, lack of interest in harvesting due to price decreases, and a scarcity of wild plants. Climatological conditions may cause year-to-year changes in goldenseal populations, but because the reproductive biology and population dynamics of the species have received little attention from botanists and plant ecologists, such changes have not been documented. In the meantime, as more growers plant goldenseal, supplies are expected to stabilize in five to ten years, the period required to harvest a crop from new plantings.
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