https://www.gosh.nhs.uk/conditions-and-treatments/conditions-we-treat/anal-fissure/
Anal fissure
Anal fissures are tiny tears in the skin around the anus and can be painful. They usually develop as a side effect of constipation. Constipation is the condition where a person passes faeces (poo) less frequently than usual and the poo is harder, drier and painful to pass.
What causes anal fissures?
They usually develop when a child is constipated. The sphincter (ring of muscle) around the anus stretches to let the hard dry poo pass, and the tissue around the anus may tear as a result.
What are the signs and symptoms of anal fissures?
Anal fissures are usually small but can be painful, as the tissue around the anus is supplied with lots of nerve endings. The tears can bleed bright red blood, which will show on toilet tissue but soon stops. After passing poo, they start to heal but can re-open the next time your child poos. They usually heal completely in a week or two, but only once the poo has softened.
How are anal fissures diagnosed?
Initially, the doctor will diagnose constipation from your child’s history. They may look at the child’s anus to see if any anal fissures are visible. Occasionally, the doctors may suggest a child has an examination under anaesthetic, to check the anus more closely and confirm that it is otherwise normal.
How are anal fissures treated?
Treatment aims to reduce the constipation, so that poo is easier to pass and the tissues around the anus are less likely to tear. This may involve a change in diet to include higher fibre foods, medicines to soften the poo so it is less painful to pass, and laxatives to stimulate passing poo.
As well as reducing constipation, there are various options for making the anal fissures less painful until they heal. A warm bath can soothe the area for a while, but it should be patted dry rather than rubbed. Creams or ointments can be soothing, but certain ones containing steroids or anaesthetics should only be used for a few days at a time.
What happens next?
Children who have developed anal fissures once are likely to develop them again. The key to preventing anal fissures is to avoid becoming constipated. Try to make sure your child has a balanced diet containing plenty of fibre and encourage them to drink plenty of fluids.