The *Huoren Shu* (Book of Living People) states that abdominal distension and fullness arise from the disharmony of Yin and Yang. Heaven possesses Yin and Yang, cold and heat; humans possess Yin and Yang, Qi and Blood. If these are not in harmony, there will inevitably be an excess of one over the other. Consequently, the cold and heat of heaven and earth will be unregulated, and the Qi and Blood within the human body will become discordant. Once Qi and Blood are discordant, myriad diseases will arise. Is it not true that distension and fullness are caused by such imbalance?

The *Liuyuan Zhengji Lun* (Treatise on the Correct Records of the Six Origins) says: "When Taiyin (Spleen Earth) prevails, central fullness occurs." It also states: "When turbid Qi remains in the upper part, distension arises." Furthermore, it says: "All dampness, edema, and fullness belong to Spleen Earth." This is because Heart and Lung belong to Yang and reside in the Upper Jiao; Kidney and Liver belong to Yin and reside in the Lower Jiao; Spleen belongs to Earth, resides in the Central Region (Zhongzhou), and is also considered Yin. As the Official of the Granary, it governs the reception of water and grain and irrigates the four other Zang organs.

The Classics state: "When food and drink enter the Stomach, they generate clear Qi which floats upward to reach the Lung, and downward to transmit to the Bladder. The essence of water distributes throughout the body, and the Five Channels circulate together." At this time, Yin and Yang are naturally harmonious; the Yang of Heart and Lung descends, and the Yin of Kidney and Liver ascends, achieving *Jiaotai* (the intersection of Heaven and Earth, or mutual interaction of Yin and Yang), resulting in a state of health without disease.

However, if invaded by the Six Evils (Wind, Cold, Summer-heat, Dampness, Dryness, Fire) or disturbed by the Seven Emotions (Joy, Anger, Worry, Thought, Grief, Fear, Fright), combined with irregular diet or sexual exhaustion causing damage, the Yin of Spleen Earth is injured. Although the Stomach receives food, it cannot transform and transport it. Thus, Yang rises spontaneously while Yin descends spontaneously. With Yin and Yang out of harmony, *Pi Ge* (obstruction and blockage of Qi mechanism) occurs. Clear and turbid Qi mix together, the Qi mechanism becomes congested, Qi transformation fails, blood stasis accumulates and generates Heat. If Heat lingers for a long time, Qi transformation transforms into Dampness. Dampness and Heat contend with each other, eventually forming distension and fullness, known as *Guzhang* (Drum Distension). Externally, the abdomen appears hard and full, but upon percussion, it sounds hollow like a drum, indicating a large, empty abdomen. The Classics say: "Abdominal distension that is large and sounds like a drum when struck refers to this condition."

There is also *Danfu Guzhang* (isolated abdominal distension resembling gu poison). The character "Gu" contains the radical for insect, seemingly implying insects eating inside, which is a fallacy. In reality, it is Qi stagnation knotted in the intestines, which is indeed difficult to treat.

The *Ling Shu: Zhang Lun* (Spiritual Pivot: Treatise on Distension) states: "Each of the Five Zang and Six Fu organs has its own type of distension, all different from one another." However, distension generally arises from rebellious Qi below, Cold Qi counterflowing upward, Ying Qi remaining stagnant, True Qi attacking Evil Qi, and the two energies clashing to form distension. This may occur between Zang and Fu organs, in the divisions of Qi and Blood, in the chest and hypochondrium, or in the skin, each having its specific pathology and presentation.

Generally, Ying Qi circulates within the vessels. If Wei Qi rebels, it causes Mai Zhang (Vessel Distension). If Wei Qi merges with the vessels and circulates within the muscle spaces, it causes Fu Zhang (Skin Distension). These diseases are caused by the Qi of the internal organs or by invasions of the Four Seasons' Qi and Seven Emotions. Regarding distension caused by dietary irregularities (hunger and satiety) leading to deficiency or excess in the Three Jiao, the treatment methods differ.

For instance: If Cold is contracted in winter causing chest oppression and fullness, with a deep and fine pulse, this is Cold Distension; treatment should focus on warming and resolving Cold. If Heat is injured in summer causing hard and full chest and abdomen, with a weak pulse, this is Summer-heat Distension; treatment should focus on clearing Heat and draining Dampness. If spleen injury from irregular eating leads to Spleen Qi deficiency, slow digestion, and slight stagnation causing distension, with a floating and slippery pulse, this is Peng Man (Bloating Fullness); treatment should use digestive methods to eliminate stagnation, and the disease will heal itself. If there is failure of ascending and descending, obstruction knotting in the chest, confusion of the Three Jiao, and blockage of urination and defecation, suddenly causing distension with a deep and hidden pulse, this is Sanjiao Distension.

Distension also has deficiency and excess patterns. Deficiency presents with loose yet firm skin, no pain but Qi fullness; treatment involves regulating Qi mechanism ascent/descent and warming/tonifying Spleen Yuan, after which recovery occurs. Excess presents with retained food internally, pathogenic excess inside, hardness and pain upon pressure; treatment should involve dispersing Qi and purging excess.

If distension results from chronic illness where Spleen Earth Qi has failed, it is a critical condition, and treatment is unlikely to be effective. For all types of distension, one must trace the origin and treat accordingly: purge the excess, tonify the deficiency, warm the cold, cool the heat, scatter the accumulation, move the stagnation. If in the Blood aspect, regulate the Blood; if in the Qi aspect, move the Qi. Only then can one ensure complete safety and avoid danger.