I ve had a dry cough for 3 1/2 months and this appeared to start with sinus infection or cold, not sure which. I ve taken steroids, antibiotics and now I m using proair hfa. My nose is constantly stopped up and the cough comes and goes. I went to an ear nose and throat dr and he said my nasal cavity was extremely swollen. That s when I took the steroids but it didn t seem to help. I ve never had allergies and wondered if I could have developed them. I have dogs in my home and I m a smoker. Any thoughts?