Tongue is a muscular organ situated in the floor of the mouth with main functions of tasting, deglutition and speech. The tongue’s colour, shape, texture and coating reveal the state of a person’s health. A healthy tongue is pink, moist and with a clear or light white coat.

Tongue diagnosing dates back to 1600 BC and is the main diagnostic tool of acupuncturists and herbalists. The traditional Chinese medicine, considers tongue as a map that corresponds to different parts of the body. The tip is connected to the heart; the sides are connected to the liver; the centre to the spleen and the back to the kidney.

A careful observation of the state of tongue, its color, shape often gives us an insight into the health condition of a person. Now the first thing to know is what is to be observed while examining tongue.

Things to be observed include: Colour of tongue whether moist or dry, any coating or furring on tongue, if the tongue large, flabby thin, thick, presence of any cracks, fissures, patches, ulcers on tongue; any deviation of the tongue, Tremors of the tongue etc.

In homeopathy tongue and taste form physical generals and helps us in constructing the patient portrait and individualizing the patient as a person. Other than representing the signs of underlying disease in body sometimes it also helps in selecting medicines wherein tongue symptoms are characteristic. The character of tongue also helps us in diagnosing the underlying miasm of the case which further helps in deciding the course of treatment. Thus to summarize, from Homoeopathic point of view a close observation of tongue helps us in :

Disease diagnosis.
Miasmatic diagnosis
Medicine selection.

Tongue as an aid in Disease Diagnosis
Color
Pale – Anaemia.
Blue – Central cyanosis.
Bluish red – Polycythemia.
Black or black hairy tongue with hyper proliferation of Filliorm – Fungal infection.
Red tongue with sharp red tip and edges – D.M., Hyperchlorohydria.
Excessive red – pellagra, acute glossitis & advanced typhoid.
Dry brown tongue – Advanced uremia.
Straw berry tongue – Scarlet fever.
Brownish pigmentation on tongue- Addison’s disease

Coating
White or greyish coating – Constipation, tonsillitis, Chronic pharyngitis.
Thick white coating – Gastritis, Enteritis.
Blanket tongue (Thick white, coated dry, flabby tongue) – Rheumatic fever.
Leukoplakia or thick white patches of various size and shapes and adherent to underlying tissue – Syphilis, Pre-cancerous ulcer.

Systemic disease
Plummer – Vinson syndrome: the mucous membranes of the tongue and the pharynx are atrophic causing dysphagia. This symptom is accompanied by spoon-shaped nails (koilonychias)
Smooth atrophy of the tongue:
With fibrosis as seen in syphilis.
Without fibrosis, viz., in hypochromic anaemia, avitaminosis etc.