Geographic tongue (also known as benign migratory glossitis) is a condition in which the tongue has a map-like appearance due to irregular smooth patches that have lost the tiny, finger-like projections that characterize the surface of a normal tongue. The patches may be red, can change location from day to day and, in some cases, can be sore. Although it can be uncomfortable, geographic tongue is not a serious disorder. Some people worry that it is a sign of oral cancer. It definitely is not.
Unfortunately, we don't know the cause of this problem. In some cases, it may be due to an allergy, and it seems to occur more often in people with psoriasis - in one study, 10 percent of psoriasis patients were affected compared to about 2.5 percent of people without psoriasis. Some cases seem to be triggered by irritation from hot or spicy foods, alcohol, or tobacco, and some may occur in response to stress. There is no specific treatment for geographic tongue. It tends to go away on its own, usually within a month, but may come back periodically. Different areas of the tongue may be affected at different times.
I wouldn't worry about your daughter's geographic tongue. Chances are it will disappear as her nutritional status improves or, if it is stress related, as she becomes more settled and comfortable in her new surroundings. Conventional treatment, if necessary, is topical prednisone, but I would first try DGL powder, a much less toxic licorice derivative.
Andrew Weil, M.D.