I have been using max air inhaler for 20 yrs. i use 1 puff at night before going to bed to help breathing. will i have anynegative long term effects ?

Are you stable on it: 20 years is a long time to use solely Maxair (pirbuterol) for breathing problems. The guidelines indicate, if you use a rescue inhaler more than 2 times a week, you need a maintenance inhaler, one that contains a steroid. It will treat the inflammation and your body will not get used to it. Talk to your doctor about your options.