Acute radiation skin injury is the most common side effect of radiation therapy in patients with chest tumors, which can be manifested as erythema, dry peeling, wet peeling, and severe ulcers. Even with current advanced radiotherapy techniques, such as intensity-modulated reverse radiation therapy (IMRT), about one-third of patients develop grade 2 or higher skin damage during radiotherapy. Radiation skin damage can cause discomfort to patients, thus affecting their daily life and reducing their quality of life. In severe cases, it can even reduce the efficacy due to prolonged treatment time. Therefore, prevention and treatment of acute radiation skin injury is a difficult problem to be solved urgently in clinical practice. Even with current advanced radiotherapy techniques, such as intensity-modulated reverse radiation therapy (IMRT), about one-third of patients develop grade 2 or higher skin damage during radiotherapy. Radiation skin damage can cause discomfort to patients, thus affecting their daily life and reducing their quality of life. In severe cases, it can even reduce the efficacy due to prolonged treatment time. Therefore, prevention and treatment of acute radiation skin injury is a difficult problem to be solved urgently in clinical practice. From previous studies, we found that taurine is an active substance that regulates normal physiological activities of the body and is widely distributed in various tissues and organs of the body. This substance has many advantages. Many previous studies have shown that taurine also has a wide range of biological functions such as anti-inflammatory, analgesic, maintaining osmotic pressure balance, improving visual function, regulating blood sugar, nerve conduction, endocrine activity, regulating lipid digestion and absorption, increasing cardiac contractility, improving immunity, enhancing cell membrane antioxidant capacity, protecting myocardial cells, etc. Considering the multiple medical values of taurine and its safety, we intend to conduct a phase I-II clinical study of taurine for external use in the prevention and treatment of acute radiation skin injury for radiation skin injury, with the study period from January 25,2024 to January 25,2027. The purpose is to evaluate the safety of taurine in the prevention and treatment of acute radiation skin injury in breast cancer patients after adjuvant radiotherapy. Possible benefits: Reduce the incidence and severity of radiation skin damage.