Library

The *Classic of Difficult Issues* (or *Huangdi Neijing*) states: New accumulations that are painful and movable are easy to cure; accumulations that are painless are difficult to cure. It also states: The great collateral vessel of the stomach is named Xuli (虚里, located at the left apex beat), piercing through the diaphragm and connecting with the lungs, emerging below the left breast. Its pulsation moves the clothing, representing the Zongqi (宗气, Pectoral Qi). If the pulse knots and spreads horizontally, there is an accumulation.

Regarding accumulations caused by food stagnation, if they accumulate gradually due to occasional dietary injury, they remain within the intestines and stomach; thus, they can be treated by promoting qi movement or purging, making treatment straightforward. However, when dietary habits are irregular and stagnation accumulates slowly, it often forms "Pi Ji" (癖积, fixed abdominal masses) between the left hypochondrium and the diaphragm, which is the pathway where Yangming Stomach Zongqi emerges. Regardless of hunger or fullness, continuous intake of food causes Yangming Stomach Qi to rebel. Consequently, Yin-cold pathogens take advantage of this weakness, and the Spleen fails to transform them. The remaining stagnation does not dissipate but combines with the fluid foam outside the intestines, condensing and failing to scatter, gradually forming Pi disease.

Initially, the condition is very subtle and often unnoticed. After a long duration, the root becomes deep and firm, making medicinal therapy ineffective. This disease is common in children in the northwest regions of China, particularly in areas where wheat-based diets prevail. This is because wheat has a cloying nature, tending to stagnate in the interstitial spaces between skin and fascia, rendering it difficult to treat. Treatment should focus on gradual dissolution using appropriate methods. One must avoid rashness and haste, refraining from reckless attacking therapies that merely injure Stomach Qi without eliminating the accumulation, thereby hastening danger.

"Pi" refers to a condition where blood transforms into water membranes, causing pain in the hypochondriac region, periodic tidal fever (Chao Re), or alternating chills and fever resembling malaria. Therefore, patients with malaria often present with this syndrome.

After a malaria attack subsides, one must wait for the heat to completely dissipate before allowing food intake. If food is consumed while heat remains, yellow fluid accumulates in the Zhongwan (中脘, CV12) region, eventually forming Pi Ji over time.

Children with harmonious viscera and strong Spleen and Stomach function have smooth Ying and Wei (营卫, Nutrient and Defensive Qi) circulation and free-flowing body fluids. Even excessive consumption of water or milk will not cause disease. However, if the Spleen and Stomach are weak, breastfeeding or feeding is irregular, and the Sanjiao (三焦, Triple Burner) fails to transport, water-dampness stagnates. Combined with cold pathogens condensing together, Pi forms. For children with constitutionally weak bodies, Xiaopi Wan (消癖丸, Mass Dissolving Pill) is indicated; for those with robust constitutions, Zheshi Aipi Wan (赭石挨癖丸, Hematite Mass-Attacking Pill) is used. Generally, most children with Pi have deficiency patterns. Purging medications should not be used frequently. Even if necessary, after slight reduction of the pathogen, Xiaopi Wan should be used to slowly dissolve the accumulation, which is an excellent method.