Quercetin is a naturally occurring polyphenol favonoid which is rich in antioxidants. It has anti-allergic functions that
are known for inhibiting histamine production and pro-infammatory mediators. Quercetin can regulate the Th1/
Th2 stability, and decrease the antigen-specifc IgE antibody releasing by B cells. Quercetin has a main role in antiinfammatory and immunomodulatory function which makes it proper for the management of diferent diseases.
Allergic diseases are a big concern and have high health care costs. In addition, the use of current therapies such as
ß2-agonists and corticosteroids has been limited for long term use due to their numerous side efects. Since the efect
of quercetin on allergic diseases has been widely studied, in the current article, we review the efect of quercetin on
allergic diseases, such as allergic asthma, allergic rhinitis (AR), and atopic dermatitis (AD).