If the tongue colour itself is purple-ish in colour and covered with a white coating. This can be an indication of Neurosis through anxiety, gastroenteritis or menstrual problems. You may also have some of the following symptoms, palpitations, dull pain around the heart, shortness of breath associated with low level anxiety. Also, fullness in the chest, pale face, spontaneous sweating, fatigue, aversion of cold temperatures and cold limbs.
If the coating is slimy and you have a discomfort in the lower abdomen, aversion to cold temperatures and cold limbs. Symptoms typically are relieved by warmth. This may be an indication of a hernia. Some hernias particularly epigastric and hiatal hernias are very difficult to diagnose.
If the tongue is very red and the white coating is greasy it can be an indicator of blood pressure problems.