Anal fissure

What is anal fissure?

An anal fissure is a small tear in the skin at the entrance of the anus (the opening of your back passage).  It usually occurs because your anus has been stretched by a hard motion due to constipation.  It is a harmless condition with no link to cancer.


What are the symptoms you can have?

Sharp pain around your anus during a bowel movement.  The pain may continue for half an hour or more and is thought to be due to spasm of the anal muscle.

You may also have slight bleeding when passing a motion.

How can it be diagnosed?

It is diagnosed by a doctor carefully inspecting the outside of your anus.  Fissures can be difficult, and if in doubt your family doctor may refer you to a bowel specialist.

If you have noticed any bleeding, you may be advised to have a telescope examination of your bowel (endoscopy) to make sure that there is no other cause of the bleeding. If it is too painful you may be examined under a anaesthetic at a later appointment.

How is it treated?

It may be treated with:

  • A prescribed cream that you apply to the area.  This may contain  a muscle relaxant to stop the spasm and allow the fissure to heal.  Steroid ointments are best avoided.
  • Simple painkillers such as  Paracetamol or Ibuprofen
  • A laxative so that the motions are easy to pass.
  • There may be a role for Botox injection if treatment with cream fails.

It is important to keep the area clean by showering twice a day.  A warm bath is recommended after each bowel movement.

Most fissures heal within eight weeks.  However, they can be slow to heal or may recur.  In these cases you may be referred to a surgeon for an operation.

What does the operation involve?

The usual operation is called a lateral sphincterotomy.  This is usually done as a day case procedure under general anaesthetic.  A portion of your anal muscle is divided by making a small cut at the edge of your anus. This will allow 90% of fissures to heal. Very rarely this is needed.

Are there any risks?

There is a small risk that the operation may cause leakage of wind or motion in the long term.

How can I prevent another fissure?

Aim to keep a soft regular bowel action by:

  • Eating enough fibre-containing foods such as fruit, vegetables and wholemeal bread
  • Drinking two to three pints of fluid a day.