Goldenseal root contains two alkaloids, berberine and canadine, with antimicrobial and mild immune-stimulating effects.⁴ However, due to the small amounts of alkaloids occurring in the root, it is unlikely these effects would occur outside the test tube. Goldenseal soothes irritated mucous membranes in the throat,⁵ making it potentially useful for those experiencing a sore throat with their cold. Human research on the effectiveness of goldenseal or other berberine-containing herbs, such as Oregon grape, barberry, or goldthread (Coptis chinensis), for people with colds has not been conducted.

Goldenseal root should only be used for short periods of time. Goldenseal root extract, in capsule or tablet form, is typically taken in amounts of 4 to 6 grams three times per day. Using goldenseal powder as a tea or tincture may soothe a sore throat. Because goldenseal is threatened in the wild due to over-harvesting, substitutes such as Oregon grape should be used whenever possible.

Elderberry has shown antiviral activity and thus may be useful for some people with common colds. Elder flowers are a traditional diaphoretic remedy for helping to break fevers and promote sweating during a cold. Horseradish has antibiotic properties, which may account for its usefulness in easing throat and upper respiratory tract infections. The resin of the herb myrrh has been shown to kill various microbes and to stimulate macrophages (a type of white blood cell). Usnea has a traditional reputation as an antiseptic and is sometimes used for people with common colds.

Wild indigo contains polysaccharides and proteins that have been reported in test tube studies to stimulate the immune system. The immune-enhancing effect of wild indigo is consistent with its use in traditional herbal medicine to fight the flu.⁶ However, wild indigo is generally used in combination with other herbs such as echinacea, goldenseal, or thuja.

In traditional herbal medicine, tinctures of various herbs, including chaparral, St. John’s wort, goldenseal, myrrh, and echinacea, have been applied topically to herpes outbreaks in order to promote healing.⁷

Herbs that support a person’s immune system in the fight against microbes and directly attack microbes include the following: barberry, echinacea, elderberry, goldenseal, licorice, Oregon grape, osha, and wild indigo.⁸

Berberine is derived from several plants, including barberry, Oregon grape, goldenseal, and goldthread (Coptis chinensis). Preliminary trials have shown that berberine can be used successfully to treat giardia infections.^9,10 In addition, test tube studies show that berberine kills amoebae, although it is not known whether this effect occurs in humans.¹¹ The amount required is approximately 200 mg three times per day for an adult—a level high enough to potentially cause side effects. Therefore, berberine should not be used without consulting a healthcare provider.

Bitter herbs are thought to stimulate digestive function by increasing saliva production and promoting both stomach acid and digestive enzyme production.¹² As a result, they are particularly used when there is low stomach acid but not in heartburn (where too much stomach acid could initially exacerbate the situation). These herbs literally taste bitter. Some examples of bitter herbs include greater celandine, wormwood, gentian,dandelion, blessed thistle, yarrow, devil’s claw, bitter orange, bitter melon, juniper, andrographis, prickly ash, and centaury.¹³. Bitters are generally taken either by mixing 1–3 ml tincture into water and sipping slowly 10–30 minutes before eating, or by making tea, which is also sipped slowly before eating.

Some bitters widely used in traditional medicine in North America include yarrow, yellow dock, goldenseal, Oregon grape, and vervain. Oregon grape’s European cousin barberry has also traditionally been used as a bitter. Animal studies indicate that yarrow, barberry, and Oregon grape, in addition to stimulating digestion like other bitters, may relieve spasms in the intestinal tract.¹⁴

Goldenseal is regarded as an herbal antibiotic and has been traditionally used for infections of the mucous membranes. While no specific research points to goldenseal as a treatment for gastritis, there is some evidence from test tube studies that berberine, an active ingredient in goldenseal, slows growth of H. pylori.¹⁵ Modern herbal practitioners now prefer alternatives to goldenseal, since the plant is threatened with extinction due to overharvesting.

Due to of its supposed antimicrobial activity, goldenseal has a long history of use for infectious diarrhea. Its major alkaloid, berberine (also found in barberry and Oregon grape), has been shown to improve infectious diarrhea in some double-blind trials.¹⁶ Negative studies have generally focused on people with cholera, while positive studies investigated viral diarrhea or diarrhea due to strains of E. coli. These studies generally used 400–500 mg berberine one to three times per day. Because of the low amount of berberine in most goldenseal products, it is unclear how effective the whole root or root extracts would be in treating diarrhea.

Because of its soothing effect on mucous membranes (including the lining of the mouth) and its healing properties, chamomile may be tried for canker sores and other mouth irritations.¹⁷ A strong tea made from chamomile tincture can be swished in the mouth before swallowing, three to four times per day. Goldenseal has also been used historically as a mouthwash to help heal canker sores.

In traditional herbal medicine, tinctures of various herbs, including chaparral, St. John’s wort, goldenseal, myrrh, and echinacea, have been applied topically to herpes outbreaks in order to promote healing.¹⁸

Berberine is an alkaloid found in various plants, including goldenseal, barberry, Oregon grape, and goldthread. Berberine exhibits a broad spectrum of antibiotic and antifungal activity in test tube, animal, and human studies.^19,20 Berberine has shown effective antidiarrheal activity in a number of diarrheal diseases,^21,22,23 and it may offer the same type of relief for the diarrhea seen in patients with chronic candidiasis. Doctors familiar with the use of berberine-containing herbs sometimes recommend taking 2 to 4 grams of the dried root (or bark) or 250 to 500 mg of an herbal extract three times a day. While isolated berberine has been studied, none of these herbs has been studied in humans with chronic candidiasis.

Teas of goldenseal, barberry, and echinacea are also sometimes used to treat infectious vaginitis. Although all three plants are known to be antibacterial in the test tube, the effectiveness of these herbs against vaginal infections has not been tested in humans. The usual approach is to douche with one of these teas twice each day, using 1–2 tablespoons (15–30 grams) of herb per pint of water. One to two pints (500–1,000 ml) are usually enough for each douching session. Echinacea is also known to improve immune function in humans.²⁴ In order to increase resistance against infection, many doctors recommend oral use of the tincture or alcohol-preserved fresh juice of echinacea (1 teaspoon (5 ml) three or more times per day)—during all types of infection—to improve resistance.

Several other herbs have been used as part of an approach for women with mild cervical dysplasia, including myrrh, echinacea, usnea, goldenseal, marshmallow, and yarrow.²⁵ These herbs are used for their antiviral actions as well as to stimulate tissue healing; they are generally administered in a suppository preparation. No clinical trials have proven their effectiveness in treating cervical dysplasia. A doctor should be consulted to discuss the use and availability of these herbs.

Goldenseal is reputed to help treat many types of infections. It contains berberine, an alkaloid that may prevent UTIs by inhibiting bacteria from adhering to the wall of the urinary bladder.²⁷ Goldenseal and other plants containing berberine (such as Oregon grape) may help in the treatment of UTIs. These herbs have not, however, been studied for the treatment of UTIs in humans.

Berberine is an alkaloid found in various plants, including goldenseal, barberry, Oregon grape, and goldthread. Berberine exhibits a broad spectrum of antibiotic and antifungal activity in test tube, animal, and human studies.^28,29 Berberine has shown effective antidiarrheal activity in a number of diarrheal diseases,^30,31,32 and it may offer the same type of relief for the diarrhea seen in patients with chronic candidiasis. Doctors familiar with the use of berberine-containing herbs sometimes recommend taking 2 to 4 grams of the dried root (or bark) or 250 to 500 mg of an herbal extract three times a day. While isolated berberine has been studied, none of these herbs has been studied in humans with chronic candidiasis.

Goldenseal and Oregon grape contain the antibacterial constituent known as berberine. While topical use of berberine in eye drops has been clinically studied for eye infections,³³ the use of the whole herbs has not been studied for conjunctivitis or blepharitis.