I've been using sinus rinse mostly daily for a couple years. dr told me to stop yesterday. what might his reasoning be? i think it does help.

Not exactly sure but: The only reason I can readily come up with, is the fact, that some saline nasal sprays contain a preservative known as benzalkonium chloride. This chemical has be shown to inhibit neutrophil function. So its possible that it prevents the helpful white blood cells present on the surface tissue of the nose from appropriately functioning and helping fight off infections.