Every morning, i have yellowish/brownish nasal mucus. ent did antibiotics, sinus ct scan, everything looks good. on nasonex (mometasone) too. what could it be?

Chronic Rhinitis: Your chronic symptoms could be secondary to poorly controlled allergic or more likely non-allergic rhinitis. Make sure you are practicing good avoidance measures if you have allergies. Try adding an antihistamine nasal spray like azelastine to your regimen. Could also try some drying agents like chlorpheniramine or methscapolamine. Mucinex (guaifenesin) can help thin secretions. See Allergist for more details.