Dr. Agustin Arrieta, Otolaryngologist with Baptist Health South Florida, explains allergies are a release of certain chemicals, such as histamine, when you are exposed to molecules or chemicals you should not be reacting to.

He says the allergy produces histamine and inflammation in the lining of the nose, and that inflammation narrows or closes off the sinus drainage area. That leads to a buildup of mucus and infection. He points out allergies can be controlled with common medicines, such as oral antihistamines, in combination with topical nasal sprays or nasal steroids. 631 07 Allergies and Sinus Infection