Nutricology Quercetin 300 formulation incorporates the highest potency quercetin available, derived from a non-citrus, hypoallergenic plant source, and stabilized with additional antioxidants so as not to auto-oxidize (degrade spontaneously). Quercetin has been shown to support the integrity of mast cells, which play a key role in controlling the release of histamine. In addition, Quercetin has been shown to reduce the production of prostaglandins and leukotrines.*  Note: Unless otherwise noted, this product has not been evaluated by the Food and Drug Administration. Our natural products are not intended to diagnose, treat, cure, or prevent any disease.