Sometimes pelvic radiotherapy can cause long-term changes. Some people may develop a split in the skin of the anus. This is called an anal fissure.

About anal fissures

Sometimes pelvic radiotherapy can cause long-term changes to the way the bowel works. Some people may develop a split in the skin of the anus. This is called an anal fissure. It can cause a sharp, intense pain when you pass a stool.

Treating an anal fissure

Your doctor can usually prescribe creams to apply to the area that will help it to heal. It is important to avoid getting constipated, because this can make a fissure worse. Your doctor may prescribe a laxative to make it easier for you to go to the toilet.

If the fissure does not get better, your doctor may advise treating it with injections of botulinum toxin A (Botox®). These are given into the tissue that lines the anus.

Some people may need a minor operation to make a small cut in the muscle around the anus. This releases the tension in the muscle and allows the fissure to heal. You usually have this operation under a general anaesthetic, and it can be done as a day patient.

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