Eating certain foods which contain hot, spicy ingredients may trigger post nasal drip.
Living in area's known to have dry air or going out doors in cold weather may cause post nasal drip.
Normal body processes, such as pregnancy may cause hormone levels to fluctuate. This may cause one to experience post nasal drip.
Certain medications may lead to one experiencing post nasal drip (birth control pills, high blood pressure medications or cholesterol lowering medications). It is important to ask your doctor if the medications you are on, can be the cause of your post nasal drip?
A deviated or irregular nasal septum may cause a person to experience post nasal drip.
Allergies may cause a person to experience post nasal drip. If these allergies are left untreated, the post nasal drip may develop into sinusitis (a sinus infection).