Nose & Sinus
Inflammation of the nasal mucous membrane is called rhinitis. The symptoms include sneezing, runny nose, and itching, caused by irritation and congestion in the nose. There are two types: allergic rhinitis and non-allergic rhinitis.
Allergic rhinitis - This condition occurs when the body's immune system over-responds to specific, non-infectious particles such as plant pollens, molds, dust mites, animal hair, industrial chemicals (including tobacco smoke), foods, medicines, and insect venom. Essentially, during an allergic attack, antibodies, primarily immunoglobin E (IgE), attach to mast cells in the lungs, skin, and mucous membranes. Once IgE connects with the mast cells, a number of chemicals are released. One of the chemicals, histamine, opens the blood vessels and causes skin redness and swollen membranes. When this occurs in the nose, sneezing and congestion are the result.
Non-allergic rhinitis - This form of rhinitis does not depend on the presence of IgE and is not due to an allergic reaction. The symptoms can be triggered by cigarette smoke and other pollutants as well as strong odors, alcoholic beverages, and the cold. Other causes may include blockages in the nose, a deviated septum, infections (in children), and over-use of medications such as decongestants.