Fungal sinus infections can cause prolonged sinus infection symptoms but do not clear up with antibiotics...need antifungal medication or herbs instead.
My own persistant sinus issues are at least partly due to severe allergies to many, many things (weeds, grass, trees, dust, animals, foods), and I find the best help from an herbal combination of Fenugreek & Thyme (product I use is called FenuThyme; I have no financial connections with this product/company).
I find if I take 2 capsules in the evening, my nose won't clog up nearly as badly at night, and 2 capsules in the morning help make it easier to breathe all day.
I should note that I'm also taking lots of antihistamines and Singulair (for Asthma & allergies), but even with all the meds, my nose still can't seem to stop running/being stuffed up (swollen). The FenuThyme is the only thing that helps with the swollen nose...I've tried antihistamine nose sprays, steroid nose sprays, neti pot, etc. and nothing helped except the FenuThyme. YMMV.
Chronic Lyme, Bart., Gluten & Sulfite Sensitivity, Many Food/Inhalant/Medication/Chemical Allergies & Intolerances, Asthma, Gut dysmotility & non-specific inflammation, Lupus, Osteoporosis, etc.; G-Tube
Meds: Flagyl, Domperidone, Claritin, Singulair, Andrographis & other herbs, homeopathy, supplements, etc.