Hi, chronic mouth ulcers suggest some kind of issue in the GI tract where the medications ur taking or the B complex vitamins in ur food is not getting absorbed into the blood stream due to probable infection in the stomach . For this both ulcer and stomach biopsy may be indicated in ur case . Also if that comes positive, proper targeted treatment for the same is available. Don't start worrying at the technical terms. I would suggest u to see a MDPhysician / gartroentrologist in ur area . Tc and lmk how things r with u .