I've Reviewed Some Of Your Previous Poster's Questions & Not

I've reviewed some of your previous poster's questions & not sure I'm any different. I'm 57 yo in relatively good health. Rx meds include doxazosin & daily cialis for BPH. The cialis is recent addition in last year. I don't have a cold, but get frequent URI's & cough. My complaint is clear fluid that leaks out of my nose apparently randomly; does not require bending over. I've never had clear/distinct sx's of a sinus infection, but believe that I have had them. Your thoughts on differential?