Suggest Treatment For Mucus In The Paranasal Sinus

i been having pressure in the ear with dizziness and also nausea and severe headaches ive been to the hospital 4 times everything is normal and had a CT scan it showed mucus in the paranasal sinus but i was given an antibiotic and it doesnt seem to be helping. I have a MRI schdule Thursday. What can be going on??? I also been having Chills!