Geographical tongue occurs when areas of the tongue become smooth and pink and irregular in shape. Against the normal furry surface of the tongue these areas create the appearance of a map, hence the name. No one really understands what causes it to happen in the first place but it doesn't need any treatment. In the majority of cases geographical tongue isn't painful. If it is then the changes you are seeing may well be due to another condition.
Oral thrush can cause areas of the tongue to become sore and creamy white patches to appear as well.
Using an oral anti-fungal mouthwash or lozenges will clear this up quickly. Redness of the tongue accompanied by discomfort may also occur when someone is anaemic. This may be due to a deficiency of iron, or folate, or the vitamins B6 and B12. These should be tested for so that if necessary any deficiency can be treated through dietary adjustments or with supplementation. Visit our extensive Ask the Doctor library of all previously asked questions and answers covering a wide range of topics.