The pathogenesis of anal fissures is due to the dry stool that cracks the anal skin, which causes the anal sphincter to spasm because the anal skin nerves are particularly sensitive, and the anal sphincter spasm causes the anal canal to be smaller, so the patient will have a thinner stool. Because the outlet becomes smaller, the stool will definitely become thinner accordingly. The symptoms of anal fissure are bleeding, pain, and constipation. Because the outlet is smaller, once dry stool comes out, it will continue to fissure the anus, causing severe pain and sometimes bleeding. At this time, if the fissure is new, you can use some swelling and pain-relieving herbal sitz baths accordingly to promote the healing of the wound. If it is an old anal fissure that has been around for a long time, the patient is recommended to have surgery.