Goldenseal (Hydrastis canadensis) was originally introduced to early American settlers by Native American tribes, who used it primarily for skin problems and as a wash for sore eyes. A member of the buttercup family, goldenseal was also commonly used to produce a golden-yellow dye.

In the early 1900's, tonics containing goldenseal became popular for the treatment of upset stomach and menstrual disorders. By the mid-1990's, a rumor began to circulate that drinking goldenseal tea would allow illicit drug users to avoid detection. Although this rumor proved to be untrue, the popularity of goldenseal soared and the herb became severely over harvested. In 1997, the Convention on International Trade in Endangered Species of Wild Fauna and Flora reported that goldenseal is at risk of becoming an endangered species. As a result, the international trade of goldenseal continues to be closely controlled and monitored.

Today, goldenseal is marketed as a tonic to aid digestion and sooth upset stomach. It is also considered a natural antibiotic and is often combined with echinacea in preparations designed to strengthen the immune system. Many professional herbalists recommend goldenseal in herbal remedies for hay fever (also called allergic rhinitis), colds, and flu. Goldenseal is considered a useful antiseptic (which is why some herbalists use it topically to disinfect cuts and scrapes) and astringent, and is commonly used to treat a host of skin, eye, and mucous membrane inflammatory and infectious conditions (such as sinusitis, conjunctivitis ["pink eye"], and urinary tract infections). It is also available in mouthwashes for sore throats and canker sores.

Goldenseal has not been thoroughly investigated in scientific studies, but some trials have looked at berberine, one of the active compounds in goldenseal. Berberine is a substance widely used in Traditional Chinese Medicine to treat dysentery and infectious diarrhea.

Laboratory studies suggest that this substance has antibacterial and immune-enhancing properties and may also have cardiovascular benefits. Berberine has been shown to dilate blood vessels and, therefore, may prove useful in the treatment of irregular heartbeat and heart failure. However, oral doses of goldenseal contain only trace amounts of berberine, so it is unlikely that the herb confers the same benefits as berberine alone. It is possible that topical goldenseal preparations and goldenseal extracts containing high concentrations of berberine may be as effective as berberine alone, but further studies are needed to investigate this possibility before any recommendations can be made.

Goldenseal is a small plant with a single hairy stem. It has two five-lobed, jagged leaves, small flowers, and raspberry-like fruit. The bitter-tasting rhizome, or root, is a bright yellow-brown in color, twisted, and wrinkled. Goldenseal can be found growing wild in rich, shady soil in the northern U.S., but is now grown mostly on farms.

Goldenseal contains a compound called berberine that kills many of the bacteria that cause diarrhea. Berberine has also been shown to kill a wide range of other types of germs, such as those that cause candida (yeast) infections, as well as various parasites such as tapeworms and giardia. Berberine may also activate white blood cells, making them more effective at fighting infection. For these reasons, berberine is used as an all-around disinfectant, both externally and internally.

Goldenseal is available in tablets, capsules (containing powdered root), alcoholic tinctures, and low-alcohol extracts. See How To Take It for directions to make topical forms of goldenseal.

Pediatric

Adjust the recommended adult dose to account for the child's weight. Most herbal dosages for adults are calculated on the basis of a 150 lb (70 kg) adult. Therefore, if the child weighs 50 lb (20 to 25 kg), the appropriate dose of goldenseal for this child would be 1/3 of the adult dosage.

Adult

• Capsules or tablets: 500 to 2,000 mg up to three times a day.
• Standardized extract: 30 to 120 mg, up to three times a day.
• Tinctures (1:5): 3 to 7 mL every day
• For disinfecting cuts, scrapes, boils, and acne: Place goldenseal extract or tincture on a clean cloth, and press the cloth gently on the affected area.
• For earaches: Mix with olive oil and use as eardrops.
• For sore throat, gums, or mouth, make a mouthwash as follows: In one cup of warm water, mix 1/4 tsp salt and 1/2 tsp, or the contents of one capsule, of goldenseal powder. (It will not dissolve completely.) Rinse and spit out.
• For vaginal irritation, make a goldenseal douche as follows: Mix 1/4 tsp. salt and 1/2 tsp, or the contents of one capsule, of goldenseal powder in 1 cup of warm water. Let the mixture settle, and strain out any suspended particles before using it. (Keep the mixture as clean as you can.) Over-douching can make you more susceptible to certain kinds of vaginal infections. See your health care provider if your symptoms do not improve after a few days.
• For eye infections and irritations, make an eyewash as follows: Use one cup of sterile water with 1/4 tsp salt and 1/2 tsp goldenseal (or the contents of one capsule), and strain out all particles. Discard if the solution becomes cloudy, which indicates bacterial growth.

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.

Pregnant or breastfeeding women as well as those with high blood pressure should use avoid goldenseal.

If used for long periods of time, goldenseal can irritate the skin, mouth, throat, and vagina. It can also reduce the number of "good" bacteria in the digestive system, which can cause nausea and diarrhea.

There are no known scientific reports of interactions between goldenseal and conventional medications.

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