What is an anal fissure?

If you see blood in your stool (poo), or have pain and discomfort in your bottom, you might have an anal fissure. An anal fissure can be very uncomfortable, but it will usually heal if you make some changes to your diet and follow some simple treatments.

Where is an anal fissure?

An anal fissure is a small tear or split in the skin that lines the anus. If the split doesn’t heal properly, it causes a small ulcer to form.

Anal fissures are very common and can occur in people of all ages and genders.

What are the symptoms of an anal fissure?

An anal fissure can cause signs and symptoms such as:

• pain during or after bowel movements, which might last for several hours
• a feeling of cramp around the anus
• blood on the stool or toilet paper after wiping your bottom
• itchiness around the anus
• a small crack or tear in the skin around the anus
• a small skin tag or lump near the anal fissure

What causes an anal fissure?

Most anal fissures are caused by trauma to the area, mainly from passing a hard or large stool during a bowel movement. Other causes of anal fissures include:

• constipation
• diarrhoea
• anal injuries
• pregnancy or childbirth
• Crohn's disease

There are other, less common, causes of anal fissures such as:

• cancer
• HIV
• tuberculosis
• syphilis
• sexually transmitted infections (STIs), such as genital herpes

When should I see my doctor?

See your doctor if there is blood on your stool or toilet paper after you have gone to the toilet, or if you have pain during bowel movements.

How is an anal fissure diagnosed?

Your doctor will talk to you and examine you, and might want to look inside your rectum and bowel. They might use an anoscope, which is a small instrument inserted into your anus to allow your doctor to have a clearer view. Or you might need to have a colonoscopy at a hospital or a day surgery centre.

How is an anal fissure treated?

There are 3 different approaches to treatment:

• conservative treatment
• botox
• surgery

Conservative treatment usually works, taking 1 to 2 months. It involves:

• eating lots of high-fibre foods and drinking lots of water to create soft stools, which will ease the pain and muscle spasm around the anus
• having warm baths and applying a muscle relaxant cream (such as 0.2% glyceryl trinitrate) to the area twice a day
• taking pain relief medication such as paracetamol if you need it

Botox is a chemical that is injected into the muscles around the anus to help them relax. Botox usually lasts for 2 to 3 months, which allows the fissure to heal.

The surgery is known as a sphincterotomy. A small cut is made into the sphincter muscle, which relieves tension. It is usually a day only procedure.

Can anal fissures be prevented?

You can prevent anal fissures by eating high-fibre foods, exercising regularly and drinking lots of water. These are all good things to do to help digestion and bowel health, which will help prevent constipation.

It's also important to wipe your bottom gently after going to the toilet.