Being that it's an aerosol and not like regular nasal sprays or saline spray bottles, I'm not AS concerned as there isn't the tendency for backwash. I DO wipe the nozzle with rubbing alcohol before and after use, but DS doesn't use it as often as he used to. We used in mainly before he figured out how to do sinus rinses, now we mainly use it when he's got a dry nose from his nasonex.