I have COPD and have used all three medications.  The singulair I no longer use since it did not seem to help me one way or the other.  I also use an albuterol inhaler for emergency symptoms.  As for the Advair 250 and Spiriva, I don't think I would be able to function as well as I do if not for those two medications.  They are both very expensive medications and I belong to two wonderful patience assistance programs through the manufacturers in order to receive both of them at little or no cost.  The problem is that I have to make sure I don't ever run out.  I ran out of the Spiriva for 19 days while I had to wait to receive a new prescription in the mail.  By the third day of not using Spiriva, I was having a more difficult time breathing and by day ten, I was unable to walk around my home without the assistance of oxygen.  By day 19, I was using oxygen 24/7 and could not take it off even for short periods of time.   After receiving the Spiriva and taking it immediately, I knew I was going to be better soon.  It has been four days since I received it, and I only use my oxygen for a few hours a day.  By the time I have been back on it for a week to ten days I won't have to use the oxygen at all (unless I catch a cold, which I pray I don't). The Advair kept me functional and I am sure it is a wonderful drug alone for some people, but without the Spiriva my life would be horrible.  I have three grandchildren, two of which are ten month old babies and a six year old boy.  When I am on my medication, I am able to babysit for any or all of them, play with the six year including playing baseball outside and take the babies for walks in their strollers.  I also have dogs that love daily walks.  When I have my meds, my life is full.  But this month when I mistakenly ran out of the Spiriva, I was acutely aware of how much I needed this medication.  I will always make sure to keep an eye on the expiration dates of my membership (this is what happened to me) and how much I have left in my prescription.  Anyhow, I  know this is not the question you asked but I had to share my experience with these medications.  I take the Advair twice a day and the Spiriva once a day.  I NEVER FORGET TO TAKE THEM ON A TIMELY BASIS AND I TAKE THEM AT THE SAME TIME.  I AM FAIRLY CERTAIN THAT THEY ARE SAFE TAKEN TOGETHER SINCE I HAVE NEVER HAD A PROBLEM DOING SO AND HAVE NOT BEEN TOLD OTHERWISE.  Good luck with your health issues.