The active ingredients of Horse Chestnut seeds are triterpene saponines (about thirty) collectively known as aescine or escine. Aescine increases vein wall resistance and reduces permeability (seepage), objectively reducing venous insufficiency symptoms (edema, swelling, etc.). Horse Chestnut seed extract is known for its phlebotonic, antioxidant, anti-inflammatory and vein wall protector effects. It inhibits elastase and hyaluronidase activity. These two enzymes degrade the vein wall and the surrounding tissues (like collagen) therefore increasing venous insufficiency symptoms and progression (like spider veins, varicose veins and hemorrhoids).

In vitro, aescine has demonstrated an anti-inflammatory effect.

Horse Chestnut seed cannot reverse varicose veins. Its effect is limited to symptom control and a slowing down of the disease progression, translating in an increased quality of life.

The German Commission E acknowledges its benefits in cases of: treatment of complaints found in pathological conditions of the veins of the legs (chronic venous insufficiency), for example, pains and a sensation of heaviness in the legs, nocturnal systremma (cramps in the calves), pruritis and swelling of the legs.