I have a cough that can be severe, coughing up mucus. I think it is sinus draining into the back of my throat, but the cough has been with me for many months. I live in NM and at altitude, 5900-6000 feet. I did not have the problem before arriving here Albuquerque/Santa Fe area, so I am preplexed. The cough is not persistent, but the back of my throat feels sore, chest is aching, die to so much coughing.