Have you been tested for allergies? I'd recommend finding a Board-Certified Allergy Specialist in your area and have them perform a skin-test on you (they place a small amount of various substances on your skin, scratch or stick it very lightly, and then measure your reactions).
If I were you, I would start taking an anti-histamine immediately, even without a diagnosis of allergies (since it's obvious you have them). In the past I have taken Zyrtec, Claritin, and Xyzal....Zyrtec seems to work best for me. You can get both Zyrtec and Claritin over the counter, and both come in a generic form (I take the generic form of Zyrtec). This helped my allergies tremendously, I would recommend taking one daily while your symptoms are in full-force, and then backing off to just whenever it's needed when your symptoms settle down.
If you ever know of a time when your allergies would bother you a great deal (like if you were going to have to do a major spring-cleaning, or doing a lot of dusting,...etc.), I would take one at least an hour beforehand. The meds work better taken in advance rather than taking them after the symptoms start.
Your cough is worrisome as it sounds like it could possibly be asthma. I thought I knew what asthma was (chest tightness, wheezing, etc.) but was shocked to find out that asthma has many more symptoms that what is normally thought of. I was experiencing your same symptoms and was eventually diagnosed with asthma. I was shocked! I would have "coughing fits" and didn't know what they were, I would get a lot of mucus in my throat and lungs and would cough and cough until it hurt.
Whatever you decide....I would advise finding a different doctor. My first "allergist" was a Pulmonologist, so if you don't have any Allergy Specialists in your area, you might try a Pulmonologist or an ENT.
I agree that you will need to keep on your meds except for Advair (which has been found to cause voice changes) and add an antihistamine which you should use regularly to maintain level in body...not just symptomatically...your home must also be completely rid of all cat dander, which may be hiding in carpets, curtains and soft furnishings. Get a lot of help with this, as you will probably get an exacerbation in syptoms as you begin this process. Try to keep home decorated if possible with clean hard surfaces that can be swiffered and mopped or wiped and wont retain mold or dust either. An air filter would certainly help.
You should also see an ENT who will better diagnose voice issues and can also help with allergy issues.
Lastly, Pay close attention to speaking voice...if it even begins to sound rough, it is an early indicator that there is a problem. Begin voice rest and
get seen quickly to avoid chronic voice injury that can lead to nodules and permanent changes to voice. Avoid cafffeine and other diuretics and consume additional water for mucous membrane health. Avoid cigarette smoke.
Also be examined for LPR which is laryngopharangeal reflux(a type of GERD) which can cause both voice loss and exacerbation of breathing problems without any sensation of heart burn or other usual symptoms associated with GERD.
Voice restoration after total loss can take up to three weeks for complete healing. Time and rest are best remedies and short course of prednisone is sometimes prescribed to aid in this process. But singing with predinisone should be avoided.
Other conditions may be underlying cause as well so it is important to see a board certified ENT who is trained to identify voice dysfunction.
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