Glutathione levels in the body may be reduced by a number of factors, including poor nutrition, environmental toxins, and stress. Its levels also decline with age. Glutathione is required by the immune system for two important reasons: it protects host immune cells through its antioxidant mechanism and it provides the optimal functioning of lymphocytes and other cells of the immune system. It is the Mother of all antioxidants. This product includes 8 injections and should be taken twice a week unless otherwise directed.