Piere tou Anal fissure (tear)

An anal fissure is a small split or tear in the skin around your anus. These are very common and can occur from infancy through to adulthood, but mostly happen between the ages of 15 and 40.

Causes of an anal fissure

Damage to the skin around your anus is the most common reason why an anal fissure develops. It can happen when you pass a hard poo and your ring of muscle (anal sphincter) is forced to open too quickly. If you have tight muscles around your anus, you may be more prone to anal fissure.

Another cause of anal fissure is diarrhoea (runny poo).

It can also happen during birth if your anus gets stretched as the baby’s head is delivered.

People with the bowel condition Crohn’s disease can also be at risk.

An anal fissure is a curable problem and does not go on to form cancer.

Symptoms of an anal fissure

The most common symptoms include:

  • sharp, intense pain during and shortly after passing a bowel motion (poo)
  • bright red blood on the toilet paper after passing a bowel motion
  • a small lump or skin tag around your anus.

If you have any of these symptoms, you need to visit your healthcare provider. It is always important to tell them if you are bleeding from your anus to rule out more serious causes.

Diagnosing an anal fissure

Your healthcare provider will assess your symptoms and look at the skin around your anus to make a diagnosis.

If a fissure is not visible but you have symptoms such as bleeding, they may arrange some tests.

Treating an anal fissure

Most fissures can be treated simply and heal within a few weeks.

Simple treatments you can try include:

  • avoiding constipation by making sure you have good dietary fibre and fluid intake
  • going to the toilet when you first feel an urge to pass a bowel motion
  • taking frequent warm baths to ease the pain and relax your anal sphincter
  • keeping your anal area clean by washing gently with water after passing a bowel motion.

Your healthcare provider may prescribe a cream containing a local anaesthetic to relieve your discomfort. Using this before going to the toilet can make it more comfortable to go.

If these measures do not work and your anal fissure gets worse, you may need further treatment. This often happens if you have ongoing spasm (contraction) of your anal sphincter muscle, which can reduce the blood flow to your skin around your anus and stop the fissure from healing. Treatment can either be medical with topical creams, or surgical.

Medical treatments

As well as the simple measures mentioned above, your healthcare provider may prescribe a cream to help relax your anal sphincter muscle. The first option is likely to be glyceryl trinitrate cream (Rectogesic), which relaxes the anal sphincter muscle and allows more blood flow into the skin to allow your fissure to heal. This does not help everyone but it is worth trying first.

The other cream that could be prescribed contains diltiazem. There is a charge for this as it is not subsidised by the government.

Surgical treatments

If the treatments above have not helped, you may need an injection of Botox (botulinum toxin) or a minor operation to make a small cut in your anal sphincter muscle (sphincterotomy). Both methods relax the anal sphincter muscle, give pain relief and allow the fissure to heal. 

Clinical review

This content was written by HealthInfo clinical advisers. It has been adapted for Health Information and Services.

Clinical advisers — HealthInfo (external link)

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