WIth regard to surgery... if you have nasal polyps you might need surgery, but any cortisone med will help shrink them so you can breathe..and maybe totally!
You have to be pro active regarding allergies... your sister shouldn't be chewing gum in church in the first place IMO, but you certainly have a right to ask her to quit with the mint!

I can't smelll but still have allergic problems..just can't tell where it's coming from half the time
TC! Drink lots of water to help flush the toxins...