What is Goldenseal?

Goldenseal (Hydrastis canadensis) has been historically used by Native Americans to help treat a variety of illnesses and ailments, such as skin disorders, ulcers, and fevers. Although wild goldenseal is difficult to find, goldenseal is now available for commercial use in the United States. The root of the plant is usually dried and can be used to make tea, capsules, or extracts. Goldenseal is also commonly available in combination with other products, such as coneflowers (Echinacea spp.). Goldenseal products are not currently classified as a controlled substance.

What is the focus of our research?

Previous research has shown that activities of some drug-metabolizing enzymes, specifically cytochrome-P450 (CYP) enzymes 2D6 and 3A4, are significantly reduced following regular administration (i.e. three times daily for 14-28 days) of a low-dose of goldenseal. Despite increasingly abundant research regarding the effects of goldenseal and goldenseal extracts on these drug-metabolizing enzymes, there is limited research about the effects of these products on drug transporters in the body. Therefore, the goal of this research is to assess the effects of goldenseal and goldenseal extracts on CYP enzyme and transporter activity in the human body using probe drug substrates. By understanding how, if applicable, goldenseal and goldenseal constituents inhibit these molecules, we can better predict how certain drugs are broken-down and subsequently cleared from the body.