Anosmia Triggered by Sinus Infection
Re loss of smell for past three years.
If you google "Google Scholar" and type in "loss of smell" you'll find a number of articles that reference that such loss of smell can OFTEN (not always) be tracked to sinus infection. I just recovered (four weeks ago) from a sinus infection (and some in bronchial passages) that I fought off for a full month before clearing. I used my old stand by ... Colloidal Silver and I make it myself so I know the strength will work. This recent infection was a very bad one and I suspect it was a lipid coated variety.
Well, during the illness, I lost my sense of smell.
That loss went on for a period of about a week and only as I gained control over the infection did I find the sense of smell return. That was the first time that had ever happened to me that I recall. But now, full recovery with elimination of virus.
I use an ear syringe to squirt the Colloidal Silver into sinus passages (called an irrigation) and let drain down back of throat or exhaling mucus first and then a second irrigation into back of throat. I never miss irrigating the ears also as I've found over the years that the eustachian tubes which connect ears to sinus cavity can also hold viruses and is a source for secondary infections. So; irrigate both sinus cavities and ear canals also.
And if the infection (if there is one) is the cause of the loss of hearing, the hearing will begin to return in time unless permanent damage was done to the nerves.
You might ask if the loss of hearing was precipitated by an infection or by medication? You said it started three years ago. Some more information for us might help give the cause. The idea of infection as cause is just a guess, after all.