what causes post nasal drip??

[lost]

people, i need your help!
can anyone list down on what causes post nasal drip?
- allergy
- sinus infection
- nasal polyps
- adenoids
anything that i left out?
i got an appointment with an ent doc soon..i want to make things clear before i go for the visit..

* p.s : i got a very bad breath after having vegetables, the smell was like a rotten veg or something, anyone here with the same problem??
it happened for almost a week then it gone then now it comes back again..
i can't take vegatables at all for the week,not even a small amout.defintely it's not my pnd, b'coz i have had pnd for more than a year already but this started around two months ago.
can anyone explain this to me?

[Twilight]

If this helps at all, I'm currently taking anti-fungal medicine and die-off effects from the yeast causes overproduction of mucus by quite a bit. So excessive mucus can also mean the expulsion off toxins.

From what I've heard diary products contribute also.

[noptical]

- deviated septum or anything else that blocks your nasal passages
- mucosal thickening that causes overproduction of mucous

[spygirl]

Depression.