The wound in the anus is mostly considered to be due to dry and hard stool, which causes anal scratches during defecation. Pay attention to local hygiene, you can wash with 1:5000 concentration of potassium permanganate solution every night to prevent the occurrence of inflammation, you can also use local erythromycin ointment or Bactrim ointment under the guidance of a doctor to apply. If the pain is severe, antibiotics should be given at the same time to prevent infection, such as oral amoxicillin capsules or roxithromycin capsules. If an anal fissure is formed, there will be severe pain every time you have a bowel movement and blood will appear afterwards. If the effect of conservative treatment is not good, consider having an anal fissure surgery if necessary. Pay attention to more rest, do not eat spicy and stimulating food, and do not drink alcohol.