Data are lacking on whether huanglian can help prevent or treat cancer.
Derived from the rhizome of the perennial herb Coptis chinensis, huanglian is used in traditional Chinese medicine for diarrhea, vomiting, abdominal fullness, jaundice, high fever, toothache, diabetes, and eczema.
Preclinical studies suggest antimicrobial, antidiabetic, antioxidant, anti-inflammatory, and anticancer effects. Alkaloids that include berberine are considered to be the active components.
Studies in humans are quite limited. Preliminary data suggest huanglian and berberine may lower blood sugar levels. Well-designed clinical trials are needed.