I Am A Breast Cancer Survivor And Am Taking Exemestane.

I am a breast cancer survivor and am taking exemestane. I am having trouble with my stomach and throat. The throat has been sore for 9 months. I have been scoped by a gastric doctor. He says the stomach is the problem not the esophagus. I have seen a ear, nose, and throat doctor. I took medicine for a month for the throat and did not get any better. My mouth stays sore too with sores on the tongue. I am on dexilant, ranitidine, and metoclopramide. My heart burn is better, but the mouth and throat is still sore. I have a bad taste in my mouth all the time. I have been on exemestane for 10 months. Could this drug be the cause of my ailments with mouth and throat?