Nasal congestion can have many causes. It is important to find out what is causing nasal congestion in order to carefully choose, preferably with the help of a doctor or pharmacist, remedies that do not harm nasal mucus and its physiological functions.
Nasal congestion is caused by inflammation from viruses, bacteria, irritants or allergic substances attacking nasal mucus. Mucus rapidly defends itself from these attacks drawing on special cells in the immune system carried in the blood and producing substances that create an unfavourable environment for the aggressors (which carry the inflammation) and also greater quantities of mucus. To carry out this rapid intense work, the mucus requires greater quantities of blood from the network of capillaries beneath the epithelium and this causes the capillaries to dilate (vasodilation).