My sinus allergies have flared, due to pollen and i just got a new small dog and i am allergic. im on zpac & still have sinus pressure. switch anti?

Decongestant: Avoidance of a known allergen (dog if you are allergic) is the best approach. ZPak is not the right drug although it does have some anti-inflammatory effects. An OTC nasal steroid would be more effective but will take a few days to reach optimal effect. If the problem remains , consult an allergist especially if you want to keep the dog and are allergic to it.