Cirsium japonicum (Japanese Thistle)

Cirsium japonicum, commonly known as Japanese thistle, is a perennial plant in the sunflower family (Asteraceae) native to East Asia. The root and aerial portions have been used in traditional herbal preparations and contain flavonoids, phenolic compounds, and other plant constituents.

In equine supplements, Cirsium japonicum may be included as a specialty botanical ingredient, but it is not used as a meaningful source of essential nutrients. Traditional applications and laboratory studies have focused on antioxidant and other biological activities, while controlled studies in horses are lacking. Ingredient identity is especially important because thistles encompass many species with different chemical profiles and safety considerations.