Postnasal drip is mucus that runs down your throat from the back of your nose. If
you have postnasal drip from allergies, try to avoid the things
you are allergic to. This could be any of the following: dust, smoke, pollen, mold, freshly cut grass, pets and certain plants, cleaning agents, chemical fumes and room deodorizers. If the allergen is not known, you may benefit from an allergy test. An over-the-counter antihistamine-decongestant combination may help provide relief.