Activated Quercetin is a unique bioflavonoid derived from plant sources. I n human cell culture studies, quercetin has been shown to inhabit histamine release.  Additional research needs to be conducted to confirm the effects of quercetin, if any, in humans.  Bromelain is a pineapple enzyme that may assist the body in times of stress.  Magnesium ascorbate is a buffered (non-acidic) form of vitamin C that helps support the immune system.