The need for a change of medication 1 month after anal fistula surgery needs to be combined with the healing of the incision. The majority of the incisions after anal fistula surgery are deep, so it is crucial to change the medication after surgery. If the incision depth is still deep 1 month after the fistula surgery, it is necessary to continue changing the medication. If the incision is basically level with the skin, there is no need to change the medication in this case, as long as you return to the hospital regularly to prevent pseudo-healing.