Excessive Throat Mucus, Used Musinex, Nasal Wash, Breathing Treaments, Nasal Sprays, Not Much Help, Has HTN, Glaucoma, Gallbladder Removed, Partial Hysterectomy. Curable?

my mother has had a problem with excessive throat mucus for about two years. She has gone to see an allergist , a pulmonologist , internist, ENT . Nothing has help with the problem. She has used musinex, nasal wash, breathing treaments, nasal sprays. There has to be connection to this problem that they are not considering. She is 76 years old, she has HTN, glaucoma , she had her galblader removed sometime ago. She had a partial hysterectomy my years ago. however, she does not have a lot of health concerns for a women of her age. If you can offer any insight, please help.