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Quick Facts

Anal Fissure


The Manual's Editorial Staff

Last full review/revision Dec 2019| Content last modified Dec 2019
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What is an anal fissure?

Your anus is the opening in your buttocks where stool (poop) comes out. A fissure is a small tear or hole. An anal fissure is a tear in the lining of your anus.

What causes an anal fissure?

Causes of an anal fissure include:

  • Passing hard or big stools

  • Repeated loose stools

  • Putting an object in your anus, such as a sex toy

  • Inflammation in the rest of the large intestine (colitis)

  • Sometimes, anal sex

What are the symptoms of an anal fissure?

Symptoms usually happen during or right after passing stool and can include:

  • Pain in your anus

  • Bleeding (a small amount)

  • Sometimes, itching

The pain can last from several minutes to several hours and happens again when you pass more stool.

Anal fissures that cause symptoms for less than 6 weeks are called acute. Those that cause symptoms for longer are called chronic.

How can doctors tell if I have an anal fissure?

Doctors can usually tell you have a fissure just by looking at your anus.

Sometimes, they will need to do an exam of the rectum with a gloved finger or an anoscope (a short tube doctors use to look in the anus). If there's bleeding, doctors look at the lower bowel with a longer scope to see if there's another cause for the bleeding.

How do doctors treat an anal fissure?

To make it easier to have a bowel movement (pass stool), you can:

  • Take medicine to soften your stool

  • Eat more fiber such as fruits and vegetables or take a fiber supplement

  • Sometimes, use laxatives for constipation (trouble passing stool)

  • Use an ointment or suppository to lubricate your anus

To help lessen the pain, you may need to:

  • Use an ointment with a numbing medicine

  • Sit in the tub with just enough warm water to cover your anus (sitz bath) for 10 or 15 minutes a few times a day

What are anal spasms?

Anal fissures can cause the muscle in your anus to cramp up (spasm). Anal spasms hurt. They also can limit blood flow to the anus. The lack of blood flow keeps the anal fissure from healing. To stop the spasms and help the fissure heal, doctors may:

  • Give you a cream to put in your anus to relax the muscles

  • Give you a shot of medicine in your anus to relax the muscles

  • Do surgery to stretch or clip the muscle in your anus if the fissure doesn't heal with other treatments

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