Inflammation of the nasal mucous membrane is called rhinitis. The symptoms include sneezing and runny and/or itchy nose, caused by irritation and congestion in the nose. There are two types: allergic rhinitis and non-allergic rhinitis.
Allergic Rhinitis occurs when the bodys 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. During an allergic attack, antibodies, primarily immunoglobin E (IgE), attach to mast cells (cells that release histamine) 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.
The word rhinitis means “inflammation of the nose.” The nose produces fluid called mucus. This fluid is normally thin and clear. It helps to keep dust, debris and allergens out of the lungs. Mucus traps particles like dust and pollen, as well as bacteria and viruses.
Mucus usually drains down the back of your throat. You’re not aware of this most of the time because it is a small amount and is thin. When the nose becomes irritated, it may produce more mucus, which becomes thick and pale yellow. The mucus may begin to flow from the front of the nose as well as the back. Substances in the mucus may irritate the back of the throat and cause coughing. Postnasal drip occurs when more mucus drains down the back of the throat.