An anal fissure is a tear in the lining of the lower rectum (anus). It can itch and cause pain. There may be bright red blood on the toilet paper after your child wipes. A fissure may form if your child is constipated and tries to pass a large, hard stool. It may also form if your child doesn't relax the anal muscles during a bowel movement.
Most anal fissures heal with home treatment after a few days or weeks. If your child has an anal fissure that takes more time to heal, your doctor may prescribe medicine. In rare cases, surgery may be needed.
Anal fissures don't cause colon cancer. And they don't lead to other serious problems. But if your child has blood mixed in with the stool, talk to your doctor.