M,
I think this question may be best directed to your doctor or health care professional or an ears, nose, throat specialist concerning specific allergies.
I have terrible sinuses and I absolutely loved these bars and had no problem whatsoever with them; but then again I am not allergic to anything. Also being allergic to the pollen could be just the smell of it and not the actual taste. I seriously doubt there is enough of the pollen in there to disrupt any nasal cavity issues. However; I would rather err on the side of precautions and discuss them with your doctor...
If you wanted to be risky you could always take a bite and adjust from there to see how you react/etc. But to be safe, I would recommend asking your doctor as there is no telling what spurs what reaction when dealing with allergies, etc.