anesthesia
"I had a colonoscopy, this was the second time. Both times Propofol worked well, I was out during the whole time, so felt no pain. One difference was this second time when I woke up, I started sneezing and my nose was running. After that my eyes started watering, and I have been having problems for days after with that with my nose running and eyes stinging. Allergy medicines have had no effect, the only thing that has helped somewhat is Nasacort.  Prior to the procedure I was not having problems with allergies.  I have found other anecdotal evidence on the internet of other people having these issues, it seems as if this is an unadvertised side effect."