Nose is filter- think all pollution
in air- molds, dust. Dust mite
poop, viruses. Nose produces mucous to capture particles. But w enuf irritation, environmental dryness, snot thickens. Best consult family doc or ent. There are nasal corticosteroid . All drainage goes over tubes middle ear. Otc_ neil med nasal wash and saline sprays to clear nasal passages.