(Disclaimer: I'm a sufferer, not a doctor.)

I'm not sure there's a really sharp distinction between allergic and
vasomotor rhinitis.  Basically, vasomotor rhinitis means your nose is
stuffy when it has no reason to be (not even an identifiable allergy).

Decongestants and steroid sprays work for vasomotor rhinitis.  Also,
I can get surprising relief from purely superficial measures such as
saline moisturizing spray and moisturizing gel.
