bronchitis
"I have ferocious allergies to all kinds of plants, mould, dust, etc.  One of my most annoying symptoms is drainage in the back of my throat.  Taking benadryl or some other "drying" agent results in the drainage forming into a very unpleasant glob on the top of my soft palate, which can be very difficult to dislodge.

My allergist's RN recommended guaifenesin for the problem, and it works wonders.  Specifically, it tends to keep the drainage more liquid, making it easier to expel (although getting it out still sounds quite gross ...)"