Increased pain on the fourth day after hemorrhoid surgery may be caused by wound growth, infection, painkiller failure and other factors. 1. Wound growth: the fourth day after hemorrhoid surgery due to the growth of tissue cells in the wound, necrotic tissue gradually shedding, will stimulate the affected area, resulting in symptoms of increased pain. 2. Infection: when the wound shows symptoms of infection 4 days after surgery, it may cause inflammatory reaction, symptoms of increased local pain, and may also be accompanied by fever, local redness and swelling. 3. painkiller failure: hemorrhoid surgery will generally be injected with long-acting analgesics, the fourth day after the operation of long-acting analgesics of the efficacy of the gradual decrease in the patient will be aggravated by the pain of the situation. The fourth day after hemorrhoid surgery, pain aggravated by a number of factors, it is recommended that timely consultation to identify the cause of the disease, under the guidance of the physician to carry out the relevant treatment.