As a traditional treatment for internal and external diseases, the medicinal bath has a long history. The Book of Rites? Qu Li: “If you have a sore on your head, take a bath; if you have an ulcer on your body, take a bath.” In the Eastern Han Dynasty, Zhang Zhongjing popularized the bathing method in clinical practice, and the Treatise on Miscellaneous Diseases of Typhoid Fever contained a formula for washing the body with lily to cure lily disease, and a bath with bitter ginseng soup to treat fox disease, etc. Li Shizhen’s “Compendium of Materia Medica” recorded the following about skin disease medicine bath: water pimples for wind-heat itching, decoction bath, get sweat; willow branches and root bark, wash wind swelling. By the Ming and Qing dynasties, the development of the medicinal bath method was mature, and the related mechanism was explored, for example, Wu Shiji’s “Rei Bo Era” put forward famous assertions such as “the theory of external treatment is the theory of internal treatment” and “although the treatment is external, it is no different from the treatment of internal”. The mechanism of action of the medicinal bath is that the drug acts on the whole body, local and affected areas, and is absorbed and travels through the meridians and blood vessels to reach the internal organs, from the surface to the inside, thus producing effects. The medicinal bath can be used to unblock the meridians, activate blood and silt, dispel wind and cold, clear heat and detoxify, relieve swelling and pain, adjust yin and yang, coordinate the internal organs, pass through the qi and blood, moisten the whole body and other health effects. Modern pharmacology has also confirmed that the bath can increase the content of certain immunoglobulins in the blood and enhance the elasticity and vitality of the skin. From modern medical research on the physiological role of the skin is to play the premise of the medicinal effect of the bath, modern medicine believes that the skin is the largest organ of the human body, in addition to the role of protection. It also has a variety of functions such as absorption, penetration, sensation, secretion and excretion, and plays an important role in the physiopathology of the human body. Research has proved that drugs are absorbed through the skin and reach the disease directly; meanwhile, a large number of nerve endings and special receptors distributed in the skin can influence the nearby receivers in the stimulation, thus regulating the function of nerves, body fluids and circulation, improving the activities of the corresponding tissues and organs to enhance the body’s resistance to disease and repair ability. In addition, the secretion, excretion and metabolic functions of the skin are involved in the excretion of metabolites such as uric acid, urea and some inorganic salts, as well as the elimination of toxins and accumulated metabolic wastes from the body, which is called “the removal of evil from the body” in Chinese medicine. The diseases treated by fumigation and medicinal bath include: psoriasis, eczema, neurodermatitis, pruritus, pityriasis rosea, nodular itchy rash, ichthyosis, herpes sweat, hyperhidrosis, acne, hormone dependent dermatitis, palmoplantar pustulosis, etc. People hope that natural drugs, especially non-invasive topical drug treatment, can solve the problems of toxic side effects, drug resistance and pharmacogenic diseases of chemical drugs. As the main body of natural medicine, bathing therapy is valued and loved by people in China and abroad. After thousands of years, it has developed its own original characteristics. Regular bathing can prevent diseases and strengthen the body, and can improve the state of subhealth, especially for the prevention and treatment of skin diseases, rheumatism and gynecological diseases have significant effect. It can also eliminate fatigue, nourish the skin, promote sleep, regulate endocrine, improve immunity, enhance body functions and prolong life for those who are not sick. According to modern pharmacological research, most of the beauty herbs contain alkaloids, II, amino acids, vitamins, phytohormones, etc., which have a nourishing and protective effect on the skin and can enhance the immunity of the skin, protect the epidermal cells and skin elasticity, and delay the aging of the skin. Beauty medicine bath has a better effect of whitening and pleasing the face, removing spots and glowing face, moistening the skin, fragrant body and deodorizing. The Emperor’s Classic of Internal Medicine says: “If you look at its external response to know its internal organs, you will know the disease”, “The birth of evil is also born in the yin, or in the yang. If the evil is born in Yang, it is caused by rain, wind, cold and heat; if it is born in Yin, it is caused by food and drink, and by the likes and dislikes of Yin and Yang”. The preface to the treatise on typhoid fever by Zhang Zhongjing, the sage of medicine and the progenitor of prescriptions, reads, “Refine the art of prescriptions to cure the ailments of the ruler and his relatives, to save the poor and the poor, and to preserve the body and to nourish its life.