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 is a small tear or split in the skin that lines the anus.

Your anus is the hole in your bottom through which faeces (poo) leaves your body.

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

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. If the split doesn’t heal properly, it causes a small ulcer to form.

Most anal fissures are caused by injury to the area. This can happen when you pass a hard or large stool (poo). Other causes 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

If you have an anal fissure you might have some of the following symptoms:

• pain during or after going to the toilet, which might last for several hours
• cramping around the anus
• blood on the stool (poo) 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

You should see your doctor if:

• there is blood on your stool
• there is blood on your toilet paper
• you have pain when you are doing a poo

Your doctor will talk to you and examine you.

Your doctor might need to examine the area and possibly look inside your anus and rectum. This may be done by inserting a gloved finger into the anus.

Your doctor may also use a small instrument called an anoscope to examine the area.

If the cause of the bleeding or pain is not clear, your doctor may refer you to a specialist. They may recommend a colonoscopy. This is a procedure to look inside the bowel, done at a hospital or a day surgery centre.

There are 3 different treatment approaches to treatment:

1. conservative treatment
2. botox
3. surgery

Conservative treatment

Conservative treatment usually works, in 6-8 weeks. It involves eating lots of high-fibre foods and drinking lots of water to soften your stools (poos). This will ease the pain and muscle spasm around your anus.

You can also take warm baths and apply a muscle relaxant cream (such as 0.2% glyceryl trinitrate) to the area twice a day. This cream is only available from pharmacists and there are some significant side effects. You should speak with your pharmacist or doctor before using it

If needed, you can take pain relief medication such as paracetamol.

Botox

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. This allows the fissure to heal.

Surgery

Your doctor may recommend surgery if other treatments have not been helpful.

Anal fissure surgery is known as a sphincterotomy. A small cut is made into your sphincter muscle, which relieves tension. You can have this as day surgery.

You can prevent anal fissures by eating high-fibre foods, exercising regularly and drinking lots of water. These all help digestion and bowel health, and help prevent constipation.

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