The purpose of the study is to evaluate the physiologic response of quinine-saline
irrigations for acute exacerbation of uncomplicated chronic rhinosinusitis following
endoscopic sinus surgery. Subjects who have previously had functional endoscopic sinus
surgery with acute exacerbation of chronic rhinosinusitis will be randomized to either a
quinine-saline or saline-placebo arm. The investigators will measure baseline and follow-up
clinical and quality-of-life outcomes for both arms, and then compare the groups at the end
of the study period. The investigators' hypothesis is that the participants in the quinine
sulfate arm will perform better on all measures as compared to the control arm.