Goldenseal comes from the Hydrastis canadensis plant native to North America. People take it as a capsule, tea, or liquid extract to support immune function and soothe mucous membranes, often at the first sign of a cold or mild digestive discomfort.
The berberine in goldenseal inhibits liver enzymes CYP2D6, CYP3A4, and CYP1A2. This can alter how the body processes many medications, leading to serious interactions. Do not give goldenseal to infants or young children; it may cause kernicterus, a severe form of jaundice. Also avoid using it during pregnancy or breastfeeding.