Geographic tongue is one of those conditions, like eczema, that mainstream doctors aren't much help at solving. I have heard several times that the mouth is the beginning of the digestive tract and problems in the mouth, like mouth sores, can indicate a more serious condition elsewhere in the digestive tract. In fact, The Celiac Sprue Association lists Geographic Tongue as a symptom of celiac.Although mainstream doctors don't know what causes this sometimes painful condition supposedly benign condition, there are several theories. One is that it is a hormonal issue as it has been noted to flare up on day 17 of menstruation. Another is that it is suggestive of a B vitamin or zinc deficiency. Others notice that it is triggered by food sensitivities. Citric acid seems to be one food that seems to trigger this condition. There was one post that geographic tongue was a symptom of an underlying yeast (candida albicans) overgrowth in the gut. Some people use it as an index of what else is going on.
Things to try:
-Ask your health food store for a zinc tally test to determine whether a zinc deficiency might be a factor.
-Try a B complex and see if it helps.
-Herbs200.com suggests using herbal teas made from aloe vera, slippery elm, goldenseal, licorice and peppermint and echinacea.
-Address an underlying yeast issue with diet and supplements.
-Look up celiac to see if you have other signs.