I have been clearing my throat for about 7 years now. I know that it is not simply a habit because it sometimes gets better (and sometimes worse). Also, if I force myself not to clear my throat when the need arises, the mucus simply accumulates and dries up, making it harder to breath.
I feel like I have mucus running from the back of my nose and accumulating at the back of my throat, but my nose is almost always dry. After I exercise, the mucus feels thicker and is harder to clear, making it difficult to breath at times. X-rays of my lungs show there is nothing wrong there. The mucus also becomes more abundant when the air is humid, or after I eat. Antacids do not work, nor does drinking milk and water (almost neutral pH) and avoiding foods like coffee and chocolate. I have tried allgery medicine, but that also failed to help. Nasal sprays give no results other than drying up my nose even more and causing nose bleeds.