The spleen opens to the mouth, flourishes on the lips and is internally and externally related with the stomach. The spleen and the stomach are the production source of qi and blood. So, inspection of mouth and lips is helpful for understanding the functions of the spleen and stomach as well as the pathological changes of qi and blood in the whole body. Inspection of mouth and lips mainly focuses on inspecting the luster, color, dryness, moisture and shape.

Color, luster, dryness and moisture:
The normal color of lips is reddish, fresh and moist. Deep red and dry lips indicates consumption of fluid by exuberant heat; purplish and brownish dry lips indicates extreme exuberance of stagnant heat; bright red lips indicates yin asthenia and exuberant fire; lips as red as cherry usually indicates poisoning by coal gas; pale lips is caused by asthenia of both qi and blood; purplish lips indicates qi stagnation and blood stasis; blackish color around the mouth indicates kidney qi on verge to exhaust; dry and fissured lips indicate impairment of fluid; swelling and painful lips or lips with ulceration and sores are often caused by fumigation of heat accumulating in the spleen and stomach.

Shape:
During the course of a disease, constant opening of mouth indicates that pulmonary and splenic qi is on verge to exhaust and that the syndrome is asthenic; difficulty in opening mouth is lockjaw seen in convulsion in sthenia syndrome.

Inspection of gums:
Gums are connected with the collaterals of yangming meridian. So inspection of gums is helpful for understanding the pathological changes of the stomach. Inspection of gums mainly concentrates on examining the color of gums. Normally, gums are light red and moist. Pale gums indicates blood asthenia; reddish swelling and painful gums indicate exuberance of gastric fire; slight swelling gums without pain indicate up-flaming of asthenic fire; bleeding and reddish swelling gums indicate impairment of the collaterals by gastric fire; bleeding gums without reddish swelling suggest impairment of the collaterals by asthenic fire.