Horse chestnut extract supports a healthy fluid balance plus antioxidant, venotonic (helpful to veins), and vaso-protective (protective of vessels or ducts) actions.The key active ingredient in horse chestnut is a substance called escin. Venotone is an extract of horse chestnut, which has been standardized and concentrated to ensure the highest quality, consistency and biological activity. Sustained release provides continuous activity while minimizing the potential for gastric irritation. Supplement Facts Serving Size 1 capsule Servings Per Container 60 Amount