goldenseal

Botanical name

Hydrastis canadensis
Parts used and where grown
Goldenseal is native to eastern North America and is cultivated in Oregon and Washington. It is seriously threatened by over-harvesting in the wild. The dried root and rhizome are used in herbal medicine.
Goldenseal has been used in connection with the following conditions (refer to the individual health concern for complete information):
Science Ratings - Health Concerns
* - Canker sores
* - Chronic candidiasis
* - Cold sores
* - Common cold/sore throat
* - Conjunctivitis/blepharitis
* - Diarrhea (berberine)
* - Gastritis
* - Indigestion
* - Infection
* - Influenza
* - Pap smear (abnormal)
* - Parasites
* - Urinary tract infection
* - Vaginitis
*** - Reliable and relatively consistent scientific data showing a substantial health benefit.

** - Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.

* - For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support and/or minimal health benefit.
Historical or traditional use (may or may not be supported by scientific studies)
Goldenseal was used by Native Americans as a treatment for irritations and inflammation of the mucous membranes of the respiratory, digestive, and urinary tracts. It was commonly used topically for skin and eye infections and has been used historically as a mouthwash to help heal canker sores. Because of its anti-microbial activity, goldenseal has a long history of use for infectious diarrhea, upper respiratory tract infections, and vaginal infections. Goldenseal is often recommended by herbalists in combination with echinacea for the treatment of colds and flu. Its benefits are most likely limited to helping ease the discomfort of a sore throat associated with these conditions. Goldenseal was considered a critical remedy for stomach and intestinal problems of all kinds by early 20th century Eclectic physicians (doctors who recommended herbs).1
Active constituents
Little research has been done on whole goldenseal root or rhizome, but many studies have evaluated the properties of its two primary alkaloids, berberine and hydrastine. Berberine, the more extensively researched of the two, accounts for 0.5–6.0% of the alkaloids present in goldenseal root and rhizome. However, the effect of goldenseal in the gastrointestinal tract is most likely localized as its alkaloids (particularly berberine) are poorly absorbed into the bloodstream, limiting any systemic antibiotic effects.2 Goldenseal also has strong astringent properties which may partially explain its historical use for sore throats and diarrhea. In test tube studies, it has shown a wide spectrum of antibiotic activity against disease-causing organisms, such as Chlamydia, E. coli, Salmonella typhi, and Entamoeba histolytica.3 Human trials have used isolated berberine to treat diarrhea and gastroenteritis with good results.4 The whole root has not been clinically studied.
How much is usually taken?
Powdered goldenseal root and rhizome, 4–6 grams per day in tablet or capsule form, is sometimes recommended.5 For liquid herbal extracts, use 2–4 ml three times per day. Alternatively, 250–500 mg three times per day of standardized extracts supplying 8–12% alkaloids, are suggested. Continuous use should not exceed three weeks, with a break of at least two weeks between each use.
Due to environmental concerns of overharvesting,6 many herbalists recommend alternatives to goldenseal, such as Oregon grape or goldthread.
Are there any side effects or interactions?
Taken as recommended, goldenseal is generally safe. However, as with all alkaloid-containing plants, high amounts (several times higher than the recommended amount above) may lead to gastrointestinal distress and possible nervous system effects.7 Goldenseal is not recommended for pregnant or breast-feeding women. Also, despite some traditional reports, goldenseal is not a substitute for antibiotics.
Drug Interactions
Certain medicines interact with goldenseal: Some interactions may increase the need for goldenseal (+), other interactions may be negative (-) and indicate goldenseal should not be taken without first speaking with your physician or pharmacist, others may require further explanation (?). Refer to the individual drug article for specific details about an interaction.
Note: The following list only includes the generic or class name of a medicine. To find a specific brand name, use the Medicines index.
Doxycycline (?)
Tetracycline (-)

Source: www.cncahealth.com