I’m just a dude with common allergies but if my nephew asked this I’d say that sometimes your nose is just sick so it makes goo, but sometimes your throat AND nose are sick and the goo makes your throat feel the even more sick. Kinda like rubbing your leg is not a big deal, but when you have a bug bite or scratch on your leg and you rub it, it hurts.
Two cups per day of mucus travels from nose down through the throat and is swallowed every day. I think it’s most wise to assume mucus / drainage never makes our throat sore but instead there are other times where other things make the throat sore. If it was mucus’s fault we live our life in daily misery.
Periodic viruses, dryness from mouth breathing, throat clearing reflex and it’s own mechanical irritation, tonsilloliths, mechanical injury from foods, potential allergic phenomena, lymph node and adenoid enlargements, referred pain from other locations, muscular spasm from the base of the tongue and hyoid region, material sometimes stuck in the vallecula, snoring is a cause of mouth breathing, chronic nasal congestion is a cause of mouth breathing are all possible things to blame. No Doubt there are more
Good question. Found ths on Quora:
Rafal Badri Medical Doctor (1976–present) Author has 782 answers and 1.5M answer views 5y
The lining of the throat gets congested. This is the inflammatory process in response to invading bacterial or viral infection. The body brings in extra blood to supply fighting white blood cells and serum that has immunity proteins named immuoglobulins. All this extra fluid volume in a space that has limited expansion will press on nerve endings. The the brain interprets this as pain.
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