The prime control of nasal resistance and therefore, of physiologic nasal obstruction, is the state of congestion of blood vessels in the inferior turbinates and the anterior nasal septum. Parasympathetic vasodilatation causes engorgement of blood vessels; sympathetic vasoconstriction relieves it.
Factors that increase the sensation of obstruction involve reduced sympathetic, or increased parasympathetic tone, for example:
Factors that alleviate blockage increase sympathetic, or reduce parasympathetic tone. These include:
Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.