Which tree's seeds are used to treat chronic venous insufficiency?

The seeds used to treat chronic venous insufficiency come from the horse chestnut tree, Aesculus hippocastanum.

The medicinal preparation is usually horse chestnut seed extract, whose key active compound is escin, also called aescin. Chronic venous insufficiency occurs when leg veins struggle to return blood to the heart, causing swelling, heaviness, pain, itching, or varicose veins. Escin is thought to support venous tone and reduce excessive fluid leakage from capillaries.

Horse chestnut is native to southeastern Europe, while the tree is now widely planted in temperate cities and parks. Its shiny brown seeds resemble edible sweet chestnuts, but they are bitter and potentially toxic when raw; the medicinal product is a carefully processed extract, not a handful of seeds.

A common mix-up is with witch hazel or butcher’s broom, which are also associated with vein and circulation products. However, the classic seed remedy for chronic venous insufficiency is horse chestnut. Clinical evidence concerns standardized extracts rather than unprocessed seeds.