A colleague, over 50 years old, usually in good health, kidney function has always been normal, one day after a cold, took a piece of Kexin, wake up in the morning, he did not feel much urine, he did not care, and then he repeatedly drank water, about 1000 ml, and still no urine discharge in the afternoon, although he did not have any discomfort for the time being, but he still felt that something was wrong, to the hospital a blood test, showing that kidney function has After hospitalization, he was diagnosed with “acute renal failure” and was required to be hospitalized, and started to urinate more after treatment with tachyphylaxis, but the damage to kidney function was further aggravated a few days after hospitalization, and then he had to perform hemodialysis twice, and only after active treatment did kidney function slowly return to normal. Imagine if he was not a doctor himself and did not pay attention to the sudden absence of urine and waited until the manifestation of uremia appeared before he went to the hospital, then it might have caused serious consequences that the kidney function was difficult to fully recover in the end. The doctor later analyzed that the cause of acute renal failure might be due to his allergy to a drug like Kexamethasone. Zheng Junhong, Department of Urology, The Second Affiliated Hospital of Shantou University School of Medicine This article is authorized by Dr. Zheng Junhong.