This combination of Quercetin and Vitamin C is a great anti-histamine, antioxidant, and anti-inflammatory. It benefits issues with the sinus and lung, and helps the process of relieve and repair. It helps as a prevention for cancer, heart disease, and many other health conditions. Quercetin and Vitamin C, being a natural anti-histamine, can be taken at high doses for excellent effectiveness at 500-1000mg per day. 60 capsules.