Sinus allergies are from th2 dominance most often. It is important to address the root cause of the imbalance (most likely pathoegnic imbalance in the respiratory system) and I personally don’t think steroids are the way to go.

The corticosteroid nasal spray will stop the sinus inflammation in the short term. However, it will promote Th2 dominance which is the exact opposite of what we want. Cortisol induces apoptosis of Th1 cells and Natural Killer cells, so whatever bacteria is in the sinuses will thrive as soon as the steroid is stopped and the bacterial sinusitis will come flaming back.

Glutamine, Glutathione, microbiome repair, soluble fiber, promotion of oral tolerance (through vagal nerve stimulation), all those things will support the sinuses long term.