I was prescribed Symbicort by a doctor at Bkk Pattaya hospital and been using it once a day for a couple of years, but sometimes I was doubtful that anything was actually coming out of the inhaler as I could never actually see or taste anything. Anyway, when I got infected with Dengue I felt so poorly I stopped using it, and to be quite honest if anything, my breathing has improved, no wheezing or whistling. Go figure.