Anal fissure

What is an anal fissure?

An anal fissure occurs when there is a split in the anal mucosa or skin, leaving the underlying muscle exposed. Anal fissures can be painful and difficult to heal, as they are continually irritated with each bowel motion.

Anal fissures are typically classified into the below sub-types:

  • Acute – occurs through constipation, difficult bowel motions and over-straining. The fissure tends to heal when bowel motions ease.
  • Chronic – these fissures occur due to an issue with the sphincter muscle. When the muscle doesn’t relax adequately following a bowel motion, an anal fissure can develop and become further irritated bowel motion. Chronic anal fissures commonly require surgical treatment.

Signs and symptoms of anal fissures

Symptoms of anal fissures may include:1

  • Pain during or after bowel motions, which may persist for several hours
  • Cramping around the anus
  • Blood on your stool or toilet paper
  • Itchiness
  • Cracking or tearing of the skin
  • Skin tag or lumps


There are several treatment options for anal fissures, which include:

  • Botox injections – Injection of botox into the sphincter muscle can assist in relaxing the muscle during bowel motions, preventing the muscle from spasm, and helping reduce pain and allowing the fissure to heal. However, the effectiveness of botox injections for anal fissures remains unclear, with research suggesting they’re helpful for 50% of patients.2 The positive effects of botox injection only lasts two to three months and needs to be repeated every few months or the fissure will recur.
  • Surgery – known as a sphincterotomy. This involves cutting into the sphincter muscle to decrease the tension, which immediately relieves symptoms. Surgery is the most effective treatment for anal fissures, with more than 90% of patients who receive surgical treatment having successful results over the long-term.2


For a full list of references, click here.
  1. healthdirect. (2019). Anal fissure. Retrieved 15 November 2019 from
  2. NHS. (2018). Treatment – Anal fissure. Retrieved 3 December 2019 from

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