Gui Zhi Ginseng Tang is from the treatise on Typhoid Miscellaneous Diseases by Zhang Zhongjing, a physician. The original formula is used to treat the symptoms of external wind-cold and superficial symptoms that damage the spleen and stomach. This formula is a combination of Gui Zhi Tang and Ren Shen Tang. Gui Zhi Tang is composed of Gui Zhi, Paeonia lactiflora, ginger, jujube, and licorice, and is a treatment for external wind-cold superficial symptoms with sweating and floating and slow pulse, and can also be considered as a formula for treating external symptoms in deficient persons. Ginseng Tang, or Li Zhong Tang, is composed of Ginseng, Atractylodes Macrocephala, Poria and Glycyrrhiza glabra, and has the effect of strengthening the spleen and dispelling dampness. Therefore, the combination of the two formulae to form Gui Zhi Ren Shen Tang is to treat the deficiency of Yang Qi in the spleen and stomach, with water and dampness stagnation and external wind and cold symptoms, which is the same disease of the exterior and the interior, but with the deficiency of cold in the spleen and stomach, and has the effect of strengthening the spleen and nourishing the stomach, warming the middle and dispersing cold and relieving symptoms. Therefore, it is beneficial to people who are prone to colds due to deficiency of the spleen and stomach. Long-term use can improve the physical constitution and enhance the immunity of the body.