An anal fissure is a small cut or tear in the lining of the anus. The crack in the skin causes severe pain and some bright red bleeding during and after bowel movements. At times, the fissure can be deep enough to expose the muscle tissue underneath.

An anal fissure usually isn’t a serious condition. It can affect people of all ages, and it’s often seen in infants and young children since constipation is a common problem in these age groups.

In most cases, the tear heals on its own within four to six weeks. In cases where the fissure persists beyond eight weeks, it’s considered chronic.

Certain treatments can promote healing and help relieve discomfort, including stool softeners and topical pain relievers.

If an anal fissure doesn’t improve with these treatments, you may need surgery. Or your doctor may need to look for other underlying disorders that can cause anal fissures.

An anal fissure may cause one or more of the following symptoms:

An anal fissure most often occurs when passing large or hard stools. Chronic constipation or frequent diarrhea can also tear the skin around your anus. Other common causes include:

In rare cases, an anal fissure may develop due to:

Anal fissures are common during infancy. Older adults are also prone to anal fissures due to decreased blood flow in the anorectal area. During and after childbirth, women are at risk for anal fissures due to straining during delivery.

People with IBD also have a higher risk for developing anal fissures. The inflammation that occurs in the intestinal lining makes the tissue around the anus more prone to tearing.

People who frequently experience constipation are at an increased risk for anal fissures as well. Straining and passing large, hard stools are the most common causes of anal fissures.

A doctor can usually diagnose an anal fissure simply by examining the area around the anus. However, they may want to perform a rectal exam to confirm the diagnosis.

During this exam, the doctor may insert an anoscope into your rectum to make it easier to see the tear. This medical instrument is a thin tube that allows doctors to inspect the anal canal.

Using an anoscope may also help your doctor find other causes of anal or rectal pain such as hemorrhoids. In some cases of rectal pain, you may need an endoscopy for better evaluation of your symptoms.

Most anal fissures don’t require extensive treatment. However, certain home remedies can help promote healing and relieve uncomfortable symptoms. You can treat an anal fissure at home by:

If your symptoms aren’t relieved within two weeks of treatment, see your doctor for further evaluation. Your doctor can make sure you have the correct diagnosis and can recommend other treatments.

A calcium channel blocker ointment can relax the sphincter muscles and allow the anal fissure to heal.

Another possible treatment is Botox injections into the anal sphincter. The injections will prevent spasms in your anus by temporarily paralyzing the muscle. This allows the anal fissure to heal while preventing new fissures from forming.

If your anal fissure fails to respond to other treatments, your doctor may recommend an anal sphincterotomy. This surgical procedure involves making a small incision in the anal sphincter to relax the muscle. Relaxing the muscle allows the anal fissure to heal.

Not all anal fissures are a sign of low-fiber diets and constipation. Poorly healing fissures or those located in a position other than the posterior and midline portion of your anus may indicate an underlying condition.

If you have any concerns about a fissure that’s not healing despite trying at-home remedies, contact your doctor to see if you need any additional tests.

An anal fissure can’t always be prevented, but you can reduce your risk of getting one by taking the following preventive measures:

  • keeping the anal area dry
  • cleansing the anal area gently with mild soap and warm water
  • drinking plenty of fluids, eating fibrous foods, and exercising regularly to avoid constipation
  • treating diarrhea immediately
  • changing infants’ diapers frequently

Anal fissures may cause sharp pain and small amounts of bright red blood with bowel movements. If it becomes a chronic anal fissure, skin tags may develop in the area associated with a chronic local infection.

Conditions associated with anal fissures include previous anal surgeries, inflammatory bowel disease, local cancers, and sexually transmitted diseases.

Some conditions that may more directly lead to anal fissures are ones that induce trauma to the area, such as vaginal delivery, anal sex, or passing hard stool.

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