I never did have a sinus infection though, just allergy
to pollen, dust, perfumes, cleaning products
, etc. Antihistamines would lessen the swelling and congestion but did not help my thinking at all.
I have solved this problem for the past 15 years by following the blood-type diet Eat Right 4 Your Type. For the first three weeks I just eliminated the six foods said to be the worst for my type, and I knew I had a solution to my problem (my brain was working).