I have been experiencing the same symptoms for the last few years. I have been to doctors, they have done every kind of exam, the dentist, taken stomach medications, changed my diet. But it remains and changes odors. Right now it smells like urine as I breathe in I smell it. I never know what, when or how strong it will be. It is really embarrassing. Sometimes it seems to be coming from my body also. I have tried nasal washing, now I'm trying baking soda. Most of the time it seems to be coming from my nose, but then when it comes from my mouth it is really horrible. Somebody HELP.