The modern day medical doctor spends very little time talking to or examining their patients. They often only look at lab reports equating numbers with drugs without asking how the patient got sick or what organs are causing the symptoms.
Bates' Guide to Physical Examination is a standard in most medical schools and is exactly what I had to study in my school. A proper physical examination can easily take over an hour! The body, as it turns out, is full of clues to help doctors diagnose and treat the unique presentation of the patient at hand. It's unfortunate that physical examination has become a lost art.
It's no surprise that the tongue is an important part of the body giving us a glimpse at internal function. It is the front end of the gastrointestinal tract giving direct information about digestive disorders and it changes color, size, and shape depending on the overall health of the blood, circulation, and even hormone levels.
This person obvious has transient bacterial growth and quit possibliy many other hostile gut pathogens. The tongue body is red, swollen, has teeth marks and is coated with a thick greasy white/yellow layer. If this patient came to me complaining of headache, allergies, and fatigue I would not prescribe pain reliever, anti-histamine, and prozac (which is likely what they would get at the regular doctor's office). I would further investigate the disruption to their digestion as this patient may be gut-centric (root cause of auxillary symptoms coming from the gut).
Keep in mind, a patient with this kind of tongue is likely suffering a lot of symptoms but their lab reports may still be normal. It all depends on what the doctor is looking for (or missing).
Holistic & Integrative Medicine