I have been on Tagrisso for 2 1/2 years. For the last 9 months, my Pet Scans have shown the cancer to be "inactive" (doctor's term). My side affects started about a year on the drug. Worse was diarrhea for almost 6 months. I finally found a supplement that stopped the diarrhea. Now, I am dealing with mouths sores. I get 4 or 5 at a times and worst ones are on tongue. I cannot eat or talk for around 5 days until they start to get better. Then, they take me off the Tagrisso for 10 days and they go away. But, then come back in a few months. Use backing soda to relieve the pain and it does help, but still still takes 20 to 12 days to recover. Has anyone found a way to prevent the mouths sores or a treatment to make them go away faster?