Anal fissure

What is anal fissure?
An anal fissure is a split in the skin of the anus, just at the opening to the outside.

What causes anal fissure?
It is a common condition that is often caused by passing a hard stool, though it sometimes occurs after diarrhoea, following childbirth or in association with other conditions. In many patients there is no obvious cause for the fissure.

What symptoms does anal fissure cause?
The most common symptom of a fissure is severe pain after passing stools. This pain may last just a few minutes at a time or several hours. Bright red rectal bleeding sometimes occurs. Itching (pruritis ani) can be a very troublesome symptom, especially at night.

How are they diagnosed?
The diagnosis of an anal fissure can usually be made by a surgeon taking a detailed note of the patient’s symptoms and performing a simple examination in out-patients. Occasionally, the surgeon may feel that the fissure is a sign of a more global problem with the pelvic floor.

How are anal fissures treated?
Many fissures heal spontaneously or with simple measures such as stool softeners, though others do not heal and become chronic. The usual initial treatment is in the form of a medicinal paste, either glyceryl trinitrate (GTN; rectogesic) or diltiazem (anoheal). These pastes should be applied to the skin around the anus and do not require insertion into the anal canal itself. It is important to complete the prescribed course even if symptoms settle quickly. Between a quarter and a half of patients using these drugs suffer with headaches; it is safe to take simple pain killers.