Sisu Ester-C Supreme Citrus Free - A powerful, immune system enhancing complex designed specifically for those who suffer from allergies, and desire the immune-boosting qualities of patented Ester-C. Sisu Ester-C Supreme is a combination of Ester-C, combined with Polysaccharides and Bioflavonoids, designed to work synergistically to effectively fight invading organisms, and provide maximum bio-availability and absorption. Can be taken as a preventative measure, or to reduce the severity and duration of colds and flus.