<s>[INST] Dear Dr, Have a nice day..! 2-3 mnths back in my mouth a burnt like black scar occured..nw its spreading to next side f the mouth....v consult a internal med dr...he advisd me to gargle with mouth wash to apply fungal cream...after applying it yesterday..nw i cant open my mouth bcoz pain...swelling....wen time f consultation he advised to chk sugar lvl thyroid ... after tat he prescribed 25gm thyroid tab sugar 110 so control myself...after tat he told if its nt going within 1 wek v can go for an biopsy...so plz advs...... 27yrs, female [/INST] Hello, thank you for consulting with Chat Doctor. This scar can be an immune mediated disease known as lichen plans, as it occur mostly in females those who are stressed. As it can be possible that because of antifungal cream the pain might have started, as it is not the treatment of it. Better you should visit a good oral medicine specialist, ad they are specialized for this kind of diseases and even get an x-ray of whole mouth done. Hope it will help you. </s>