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Anal Fissures

What is an Anal Fissure?

An anal fissure is a split or tear in the lining of the anal canal (rectal opening).

When does an Anal Fissure occur?

A fissure most commonly occurs after an episode of constipation, but it can happen after an attack of diarrhea. A fissure begins on the surface and usually heals rapidly on its own. Sometimes fissures may deepen to reach the underlying sphincter muscle (the muscle around the anal canal). It is not completely understood why some fissures heal and others do not. One major factor is persistent constipation or diarrhea, which can prevent healing. In addition, each time stool passes, the muscle goes into spasm, tightening the anal canal. If the sphincter muscle does not relax and the anal canal remains too tight, the fissure opens again with each bowel movement.

Rarely, a fissure can be caused by Crohn's disease or an infection. Treatment for the underlying disease usually relieves the fissure. Fissures very rarely become infected and they do not become cancerous.

Anal Fissure Symptoms

  • Rectal pain: people often describe it as burning or tearing pain with a bowel movement. The pain may last for minutes or persist for hours after a bowel movement. The pain that lasts after a bowel movement is caused by the spasm in the sphincter muscle.
  • Rectal bleeding: It is usually small amounts of bright, red blood that can be seen on the toilet paper or in the toilet water.
  • Swelling: swelling at the outer end of the fissure can result in a skin tag. It may be noticed when cleaning the rectal area.
  • Itching: Discharge may result as the fissure alternately heals and reopens, causing itching.

Treating Anal Fissures

Most superficial fissures heal without treatment, but some become chronic and cause ongoing discomfort. The first step is to correct the constipation or diarrhea and treat any underlying disease. A high-fiber diet or dietary bulk agent with plenty of fluids is recommended. A topical anesthetic ointment may help relieve the pain. The spasm may also be relieved by sitting in a warm bath several times a day. These measures usually result in healing. If they do not or the symptoms return, surgery may be required. Your doctor will discuss this with you.

Preventing Anal Fissures

  • If constipation is a problem, eat foods high in fiber. Drink 8 to 10 glasses of fluid that do not contain caffeine or alcohol. Your doctor may recommend a commercially available natural fiber product to increase your fiber intake.
  • If symptoms do recur, take warm baths. This will help to reduce the spasm and lessen the pain.
  • If your doctor recommends an ointment, apply it directly to the painful area.