In the methods of TCM for regulating the spleen and stomach, there are two fundamental approaches: one is warming and tonifying kidney yang, commonly using Sijitu Decoction; the other is warming and promoting heart yang, with the representative formula being Cinnamon-Garlic Decoction. They are effective because the transportation and transformation function of the spleen and stomach relies on the support of the whole body's yang qi, especially the warming of heart yang and kidney yang.

According to Traditional Chinese Medicine (TCM), the "spleen governs transformation and transportation." However, the spleen itself is an organ that "prefers dryness and has an aversion to dampness," requiring a warm environment to function properly. The heart represents the "monarch fire" and governs the yang energy of the entire body, while the kidneys serve as the root of primordial qi, storing the "fire of the gate of vitality." The spleen and stomach are located in the middle energizer, situated precisely between the heart and kidneys. Therefore, as long as heart yang and kidney yang are sufficient, spleen yang will naturally receive warmth and nourishment, thereby enhancing its transformative and transport functions.

The Si Ni Tang (Four-Cold Decoction) originates from the *Treatise on Cold Damage*, with Fu Zi (Aconite) and Gan Jiang (Dried Ginger) being highly pungent and intensely warm ingredients. It excels in warming and tonifying kidney yang, dispelling cold, and aiding the fire. It is particularly suitable for conditions where kidney yang is deficient and unable to warm the spleen. Such individuals often exhibit symptoms such as cold hands and feet, sore waist and knees, aversion to cold in the abdomen, and clear, long urination, which are indicative of spleen-kidney cold deficiency. By tonifying kidney yang, the "stove" below the spleen and stomach is provided with sustained heat, allowing food and medicine to be better digested and absorbed.

The Gui Zhi Gan Cao Tang (Cinnamon Twig and Licorice Decoction) also originates from the *Treatise on Cold Damage*. Although it contains only two herbs—Gui Zhi (Cinnamon Twig) and Gan Cao (Licorice)—Gui Zhi is pungent and warm, promoting yang, while Gan Cao is sweet and neutral, harmonizing the middle. When combined, they transform pungent and sweet into yang, with the primary focus on invigorating heart yang and warming blood vessels. Sufficient heart yang can descend to warm the spleen and stomach, aiding in the transformation of food and drink and the transportation of qi and blood. It is particularly suitable for conditions caused by insufficient heart yang and lack of warmth in the spleen, such as stomach cold, poor appetite, and poor digestion.

In a clinical case, I treated a middle-aged male patient who had suffered from a fear of cold in his stomach for years, experiencing diarrhea after consuming even a small amount of cold food. He often felt cold hands and feet and was prone to palpitations and fatigue. The syndrome was diagnosed as heart-spleen yang deficiency, and the treatment involved modifying and combining Gui Zhi Gan Cao Tang with Fu Zi Li Zhong Tang (Aconite and Ginger Middle Jiao Decoction). Two weeks later, he reported significant relief in his stomach discomfort and warmer hands and feet, along with improved digestive function.

It should be noted that Si Ni Tang is inclined to warm the kidneys and restore yang, with a stronger pharmacological action, making it suitable for individuals with obvious yang deficiency and cold excess. Gui Zhi Gan Cao Tang, on the other hand, is more effective in warming and promoting heart yang, with a relatively milder pharmacological action. Specific use should be based on syndrome differentiation and is not recommended for self-medication.