Hi, I have been to the doctors today, with burning in my mouth and a coated tounge and strange taste. Doctor gave me Nystan and said if it doesn't go away, she will write to neurologist, as could be ms related or tecfidera related. Has anyone had oral thrush before ? As I have been on Tecfidera for a few years, just seems strange if causing problems now. Or is it ms related?? Any help please??