Although goldenseal root is one of the most popular herbs sold today, it is taken almost entirely for the wrong reasons. Originally, it was used by Native Americans both as a dye and as a treatment for skin disorders, digestive problems, liver disease, diarrhea, and eye irritations. European settlers learned of the herb from the Iroquois and other tribes and quickly adopted goldenseal as a part of early colonial medical care.

In the early 1800s, an herbalist named Samuel Thompson created a wildly popular system of medicine that swept the country. Thompson spoke of goldenseal as a nearly magical cure for many conditions. His evangelism led to a dramatic upsurge in demand, followed by over-collection and decimation of the wild plant. Prices skyrocketed and then collapsed when Thompsonianism faded away.

Goldenseal has passed through several more booms and busts. Today, it is again in great demand, but now it is under intentional cultivation.

Goldenseal contains a substance called berberine that has been found to inhibit or kill many microorganisms, including fungi, protozoa and bacteria.1,2,10-14,22 On this basis, contemporary herbalists often use goldenseal as a topical antibiotic for skin wounds, as well as to treat viral mouth sores and superficial fungal infections, such as athlete’s foot. However, there is no direct scientific evidence that goldenseal is effective for any of these purposes.

Note that goldenseal probably is not likely to work as an oral antibiotic, because the blood levels of berberine that can be achieved by taking goldenseal orally are far too low to matter.3 However, goldenseal could theoretically be beneficial in treating sore throats and diseases of the digestive tract (such as infectious diarrhea) because it can contact the affected area directly. Similarly, since berberine is concentrated in the bladder, goldenseal could be useful for bladder infections. Nonetheless, again there is as yet no direct evidence that goldenseal is effective for any of these uses.

Extremely weak evidence (far too weak to rely upon at all) suggests that goldenseal or berberine may be helpful for various heart related conditions, including arrhythmias, congestive heart failure, high cholesterol, diabetes, and high blood pressure.15,16,21,24 Similarly, infinitesimal evidence hints that goldenseal could be helpful for conditions in which spasms of smooth muscle play a role, such as dyspepsia (nonspecific stomach distress) and irritable bowel syndrome, as well as various forms of pain caused by inflammation.17,18

Ironically, goldenseal’s most common uses are entirely inappropriate. Goldenseal is frequently combined with the herb echinacea to be taken as a "traditional immune booster" and "antibiotic" for the prevention and treatment of colds. However, as the noted herbalist Paul Bergner has pointed out, there are three things wrong with this packaging:

  • There is no credible evidence that goldenseal increases immunity. Only one study weakly hints at an immune strengthening effect.19
  • Colds are caused by viruses and don't respond to antibiotics, even if goldenseal were an effect systemic (whole body) antibiotic, which it almost certainly isn't.
  • Goldenseal was never used traditionally for the common cold.

The other myth that has helped drive the sales of goldenseal is the widespread street belief that it can block a positive drug screen. The origin of this false idea dates back to a work of fiction published in 1900 by a pharmacist and author named John Uri Lloyd. In Stringtown on the Pike, a dead man is found to have traces of goldenseal in his stomach. In fact, he had taken goldenseal regularly as a digestive aid, but a toxicology expert mistakes the goldenseal for strychnine, and deduces intentional murder.

This work of fiction sufficed to create a folkloric connection between goldenseal and drug testing. Although the goldenseal in the story actually made a drug test come out falsely positive, this has been turned around to become a belief that goldenseal can make urine drug screens come out negative. A word to the wise: it doesn't work.