If you are taking Duoneb there is no point in taking
Spiriva because
Spiriva is related to the ipratropium that is
a consitituant of Duoneb. Also
Spiriva is extremely drying which may be why you are feeling so uncomfortable.
To be using Duoneb five or six times a day you would have to be close to death. Obviously you aren't, so you can cut back without any problem. I have serious COPD and my use of Duoneb averages 3.5 vials daily.
The big question is - how bad is your COPD?