An anal fissure is a break or tear in the mucous membrane lining of the anus that will likely result in symptoms of pain and bleeding during and after a bowel movement, discomfort with urination, and a visible tear in the anus that may have a foul-smelling discharge.
What Is Anal Fissure?
An anal fissure is a break, or tear, in the mucous membrane lining of the anus. The anus is the opening at the end of the digestive tract where stool leaves the body. A fissure is caused primarily by constipation, which leads to straining to pass large hard stools; trauma caused by insertion of objects or by anal sex; and illnesses such as any type of inflammatory bowel disease or sexually transmitted disease.
Symptoms include pain and bleeding during and after a bowel movement, discomfort and difficulty with urination, and a visible tear resembling a crack in the anal tissue that may have a foul-smelling discharge.
Treatment primarily involves limiting constipation and thus straining by consuming more fiber and fluids, as well as easing anal irritation by soaking in a warm bath and gently cleansing the tissues of the anus. In some cases, medicated creams or suppositories may be prescribed.
You can treat anal fissures "conservatively", meaning without need for prescription treatment. It consists of increasing fiber and water in your diet, taking sitz baths, and using a topical analgesic (pain-relieving cream). Stool softeners can also make passing stools less uncomfortable.
Anal Fissure Symptoms
The symptoms of anal fissures are usually very noticeable and can be particularly disturbing and painful. These symptoms include:
- Sensation of tearing, ripping, or burning during bowel movement: Upon the inciting bowel movement, you may feel the painful tearing of the anus as you defecate.
- Acute anal pain: Anal pain caused by anal fissures is usually present and noticeable at rest. This pain is provoked severely by defecation and may last several hours after each time you defecate due to re-injury to the site of the fissure. Such pain can cause children to become afraid of going to the bathroom and may lead to fecal impaction.
- Anal bleeding or bloody stools: Anal fissures usually bleed a small amount of blood, especially upon the stretching associated with defecation. You may notice bright red blood on the stool or as spotting blood on your toilet paper.
- Anal itching and irritation: Injury and subsequent healing of the tear may lead to itching and general irritation around the site of anal injury.
Anal Fissure Causes
Anal fissures are one of the most common causes of anal pain and bleeding. This is generally a benign condition, typically caused by trauma or underlying conditions.
About the gastrointestinal tract
When you eat food, your body digests it systematically through a long passageway, your gastrointestinal tract. The last few areas through which food is processed and turned into waste are your colon and your rectum. Once the food is ready to be excreted as feces, it passes through your anus. The anus acts as a "sphincter." It has a ring of muscle which squeezes to prevent leakage of feces during your everyday routine until it is time to go to the bathroom.
If you develop an anal fissure
When you develop a tear in your anus, this tear can extend deeply down to this layer of circular muscle. Such a tear causes irritation of the "internal sphincter" making it spasm and clamp down further. This, unfortunately, causes the tear to become deeper and constricts blood flow to the area, preventing healing. An anal fissure that lasts six weeks or less is termed "acute." If it lasts longer than six weeks, it is called a "chronic" anal fissure. Common causes include trauma and related conditions.
If you pass a large, hard stool or severe diarrhea, this can stretch the anus to the point that it tears. Similarly (and less common), the insertion of a foreign body or anal intercourse can cause traumatic stretching of the anus and lead to fissure formation. The common theme here is increased pressure in the anal canal leads to stretching, spasm, and trauma.
A less common cause of anal fissure is an underlying medical condition. Crohn Disease, specifically, is known to be a cause of anal fissures. While many people with Crohn disease develop anal fissures, most anal fissures are not secondary to this inflammatory bowel disease.
Who is most likely to be affected
Anyone can develop anal fissures and one in five people are estimated to experience an anal fissure at some point in their life, however, they are more likely in:
- Individuals with Crohn Disease
- People who are frequently constipated may also develop anal fissures due to their hard bowel movements
Treatment Options and Prevention for Anal Fissure
Anal fissures can usually be managed with lifestyle change and topical medications, as described below. More severe, chronic, or recurrent cases may require surgery.
Various at-home treatments may be effective enough to provide relief of your symptoms.
- High fiber diet: Eating a diet higher in fiber (which can be found in fruits in vegetables or can be supplemented) can soften your stools and help diminish recurrent trauma and stretching caused by .
- Stool softeners: Stool softeners and laxatives can also help you pass stool without worsening your existing anal fissure, allowing it to heal more effectively.
- Sitz baths: A sitz bath is when you submerge your anus in warm water for 10 to 15 minutes. This should be done two to three times a day. You should not add anything to the water. The warm water of the sitz bath causes dilation of the blood vessels in the anus, allowing for better healing.
Treatments from a medical provider
If at-home treatments are not enough for relief, you can consult your physician.
- Topical analgesics: Topical pain medications will not help your anal fissure heal faster, but they can reduce your discomfort as treatment proceeds.
- Topical vasodilators: As described above, part of the difficulty with treating anal fissures is that the spasm by the anal sphincter to the site of injury, slowing the healing process. A topical vasodilator, such as nifedipine or nitroglycerin, causes the blood vessels by the fissure to dilate, enhancing blood flow to the region.
- Botulinum toxin: Botulinum toxin (otherwise known as Botox) can be injected into the anal sphincter. This toxin causes relaxation of the muscle, allowing more appropriate healing. This is reserved for chronic anal fissures which .
- Surgery: In the case of chronic anal fissures, surgery may be performed to release the strain on the anal sphincter via a small incision or to surgically remove the fissure. This is a more extreme step after medical management has failed.
The best way to prevent anal fissures is to prevent severe constipation or diarrhea. You should try to eat a high-fiber diet, as this will cause softer stools. Fiber can be found in fruits and vegetables or can be supplemented via commercial fiber products. Stool softeners, such as docusate, can also be used to help with prevention. Be sure to drink adequate fluids as well.
Most acute anal fissures resolve within a few weeks. However, up to 40 percent of anal fissures may not resolve immediately due to poor healing in this area and the repeated trauma of defecation. These "chronic" anal fissures may become persistent problems requiring more active intervention.
When to Seek Further Consultation for Anal Fissure
Anal fissures are not an emergent condition. However, you should be careful if you are having symptoms consistent with a fissure, especially bleeding from your anus.
If you are experiencing persistent bleeding from the anus or rectum
More serious conditions can present as bleeding from the anus or rectum, such as colon cancer. People with this symptom can benefit from seeing a physician for a proper examination and/or visualization of the colon and rectum via sigmoidoscopy or colonoscopy. This is the only way to rule out other more serious conditions.
Additionally, anal fissures can be a presenting symptom of inflammatory bowel disease (specifically Crohn disease) and it will take a visit to a physician to ensure your condition is benign.
- Nelson RL, Thomas K, Morgan J, Jones A. Nonsurgical therapy for anal fissure. Cochrane. Published February 15, 2012.
- Steele SR, Madoff RD. Systematic review: The treatment of anal fissure. Aliment Pharmacol Ther. 2006;24(2):247-257.
- Solomon M, Smith S. Review: Medical therapies are less effective than surgery for anal fissures. BMJ. 2004;9(4):online.
- Diagnosis and management of anal fissures. Am Fam Physician. 2003;67(7):1608-1611.
- Anal fissure symptoms and causes. Mayo Clinic. Published January 6, 2018.
- Anal fissure. American Society of Colon and Rectal Surgeons.
- Anal fissures. Cleveland Clinic. Updated April 24, 2014.
- Stewart DB. Patient education: Anal fissure (beyond the basics). UpToDate. Updated November 14, 2017.