Quercetin is one of the many types of flavonoids or plant pigments that give fruits and flowers much of their colour. It is a potent antioxidant that can help to protect your body from damage caused by free radicals. Antioxidants can neutralise free radicals and can reduce or even help prevent some of the damage they cause. Quercetin Assist acts like an antihistamine as well as an anti-inflammatory in that it can assist against inflammation and allergies. It also can fight off viruses, bacterial infections and fungus.