How to get rid of a congested/mucus filled cough?

okay ever since the month of may in 2011, i had this horrible cough. It started out as a cold from my brother. Then it lead to having a sore throat.. Then i got a bunch of mucus in there and its been there ever since.. I always cough out the mucus into the toliet but its still there! I cough like a guard dog and its really embaressing. I went to the doctor in early june but they gave me medicene that was supposed to cure it but it didnt give a result. I also got a ear infection, but the medicene cured that, but not my terrible cough. But sometime it isn't there.. Sometime i wheeze when i breathe, the other I dont... PLEASE HELP!