What is an anal fissure?

An anal fissure is a tear in the lining of the lower rectum (anal canal) that causes pain during bowel movements. Anal fissures don’t lead to more serious problems.

Most anal fissures heal with home treatment after a few days or weeks. These are called short-term (acute) anal fissures. If you have an anal fissure that hasn’t healed after 8 to 12 weeks, it is considered a long-term (chronic) fissure. A chronic fissure may need medical treatment.

Anal fissures are a common problem. They affect people of all ages, especially young and otherwise healthy people.

What causes an anal fissure?

Anal fissures are caused by injury or trauma to the anal canal. Injury can happen when:

• You pass a large stool.
• You are constipated and try to pass a hard stool.
• You have repeated diarrhoea.
• You give birth. (Child birth can cause trauma to the anal canal.)

Fissures can also be caused by a rectal exam, anal intercourse, or a foreign object. In some cases, a fissure may be caused by Crohn’s disease.

What are the symptoms?

You may have:

• A sharp, stinging, or burning pain during bowel movements. Pain from a fissure may be quite severe. It can be brief or last for several hours after a bowel movement.
• Itching.
• You may see a small spot of bright red blood on toilet tissue or a few drops in the toilet bowl. The blood from a fissure is separate from the stool. (Very dark, tarry stools or dark red blood mixed with stool may be a sign of a more serious problem.) Tell your doctor if you have any bleeding with a bowel movement.

Sometimes an anal fissure may be a painless wound that won’t heal. It may bleed from time to time but cause no other symptoms.

How is it treated?

Most short-term anal fissures can heal with home treatment in 4 to 6 weeks. Pain during bowel movements usually goes away within a couple of days after the start of home treatment.