Hi Doctor, I ve suffered with allergic rhinitis for many years, resulting in a loss of smell. However, after using Betnesol my smell returns (I put one drop in each nostril once a day), but how long should I use it for and what will happen if I were to use it continuously over a long period? I can t tell you how my quality of life improves when I can smell and taste once more but conscious that I shouldn t over do it! Thanks.