Night Blindness in Traditional Chinese Medicine

Choppy (Se), Fine (Xi), Weak (Ruo)

The tongue body is typically pale or pale-white, reflecting the overall Blood deficiency. It may be slightly thin due to insufficient Blood to fill the tongue body. The coating is usually thin and white, which is relatively normal and confirms the absence of Heat or Dampness. In more severe or prolonged cases, the tongue may appear slightly dry if Blood deficiency is beginning to affect fluid nourishment, but in the typical presentation it retains normal moisture. The sides of the tongue (corresponding to the Liver) may appear particularly pale.

Choppy (Se), Fine (Xi), Wiry (Xian), Weak (Ruo)

The tongue is characteristically pale, especially on the sides (which correspond to the Liver in tongue geography). In mild cases, only the sides may appear notably paler than the centre. In more pronounced deficiency, the entire tongue body is pale. The tongue tends to be thin and slightly dry, reflecting the lack of Blood to moisten and fill it. The coating is typically thin and white, which is normal and indicates the absence of pathogenic factors like Heat or Dampness. Maciocia has noted that in rare cases the tongue sides may take on an 'orangey' hue, indicating severe Liver Blood deficiency. In clinical practice, concurrent Dampness or Phlegm may make the tongue appear less thin than expected.

Fine (Xi), Rapid (Shu), Wiry (Xian)

The tongue is characteristically red, thin, and dry with little or no coating. The sides of the tongue (corresponding to the Liver/Gallbladder area in tongue geography) tend to be redder than the rest of the body. The coating is often completely absent or partially peeled, revealing the red, glossy surface underneath. This mirror-like or geographic coating reflects the depletion of Yin fluids. In milder cases, a thin, scanty, rootless coating may still be visible. Cracks may appear on the tongue surface, particularly in the centre, indicating chronic fluid depletion.

Choppy (Se), Fine (Xi)

The tongue body is pale overall, reflecting Blood Deficiency, and the sides of the tongue (corresponding to the Liver area in tongue diagnosis) may appear particularly pale or, in chronic cases, take on a slightly orange tint. The tongue body tends to be thin due to insufficient Blood nourishment, and teeth marks may appear on the edges when Spleen Qi is notably weak. The coating is typically thin and white, which is normal but may appear slightly dry rather than moist, because Blood is a major component of the body's moistening fluids. In mild cases, the tongue may look almost normal except for its paleness and dryness.