Diosmin and Hesperidin are used widely in Europe for decreasing the appearance of varicose veins and spider veins, and also hemorrhoids. Hesperidin is the predominant flavonoid in lemons and oranges. The peel and membranous parts of these fruits have the highest hesperidin concentrations. Hesperidin is classified as a citrus bioflavonoid. Hesperidin, Diosmin and other flavonoids thought to reduce capillary permeability and to have anti-inflammatory action were collectively known as vitamin P. These substances, however, are not vitamins and are no longer referred to, except in older literature, as vitamin P.