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NOTE: Some of the information provided contains graphic, medical images which individuals may find upsetting

An anal fissure is a common condition where there is a tear in the lining of the anal canal. Fissures may be caused by constipation and passage of hard stool, or diarrhoea and passage of frequent stool.

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What is an anal fissure?

An anal fissure is a common condition where there is a tear in the lining of the anal canal. Fissures may be caused by constipation and passage of hard stool, or diarrhoea and passage of frequent stool.

What are the symptoms?

The symptoms of a fissure are pain, especially when passing a bowel motion, and some bleeding. Occasionally, people experience discharge of abscesses in association with a fissure.

How is the diagnosis made?

The diagnosis is usually made by careful questioning and analysis of symptoms. It will usually be necessary to examine the anus (back passage) with a finger and sometimes it is necessary to examine the anus with a telescope. If this is uncomfortable then it may be performed under a general anaesthetic (put to sleep).

How can it be treated?

At least 50 per cent of fissures heal either by themselves or with non-operative treatment, including application of special medicated cream, use of stool softeners, and avoidance of constipation. Two ointments are commonly used. The first is 0.2% GTN (glyceryl tri-nitrate), which may give you a headache as a side effect. This can be relieved by taking paracetamol half an hour before using the cream.

The second ointment is Diltiazem and the most common side effect of using this is itching around the back passage.

These creams are often used for 6-8 weeks. After this you see the surgeon again to ensure the fissure has healed. A second course of these ointments may be required. Some fissures, if they do not respond to these methods, may require an operation.

What does surgery involve?

A common operation for this condition is to inject Botox (similar to that injected in the face to reduce wrinkles) around the sphincter muscles of the anus. This can help heal the fissure in some cases. Repeated injections may be required to get the fissure to heal. The most common complaint with Botox is an inability to control the passage of wind immediately following the injection and some leakage from the back passage. Another operation commonly used is a lateral anal sphincterotomy. This involves cutting a part of one of the anal muscles which helps the fissure to heal by preventing pain and spasm and which improves the blood supply to the skin. Cutting this muscle rarely interferes with the ability to control bowel movements and can often be performed without an overnight hospital stay. It is often used if botox fails to help the fistula to heal.

Further information