It may be caused by diarrhea, the passing of large bowel movements, or childbirth trauma. It may also be a side effect of medical treatment. Chronic fissures may show an external skin growth at their upper ends.
Fissures are common in newborns and children with constipation.
Normally the application of a local anesthetic ointment and the use of stool softeners are sufficient treatment for an anal fissure. Occasionally in chronic cases, surgery may be required and is usually curative.