Afterthought. In place of Advair I use natural anti-inflammatories and mucolytics. Works well and no side effects.
I don't know if this is pertinent, but Advair caused such extreme coughing (almost incapacitating bronchitis) that I stopped using it. As for Spiriva, I find it extremely drying. I only use it every fourth day. On that regimen it helps. My lung health is actually much better and I am more comfortable since I gave up Advair, and my coughing is moderate. Advair also caused me to develop adrenal fatigue, which was quite dreadful, and I am still recovering from it. Like you I have 50 per cent lung capacity and am thinking about getting oxygen, at least for sleeping.