|MadSci Network: Anatomy|
Your nasal mucosa is constantly secreting mucous. It acts as a protective barrier for the mucosa and filters dust and other particles in the air to prevent them from reaching your lungs. This mucous can then be swallowed blown or in some cases dry up and be picked out.
The condition you describe sounds like it should be evaluated by a medical professional as you may have an infection, rhinitis (allergic or other type) or some other condition. It may just be the normal mucous production described above, but it is impossible to make a medical diagnosis via the internet. Please seek evaluation by a physician to determine the cause of these symptoms.
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