Anal Fissure Diagnosis and Treatment

Medically Reviewed by Neha Pathak, MD on September 16, 2021

Trauma or injury can stretch the anal canal and create a tear in the lining of the anus. These tears, known as anal fissures, usually come from passing large or hard stools. They can cause pain and bleeding during and after bowel movements.

 

You can easily mistake these symptoms as signs of other conditions, such as hemorrhoids.

You might not be comfortable telling these problems to a doctor, but it's important to do so. That way, they can rule out more serious conditions.

In most cases, discussing your symptoms can give your doctor enough information to diagnose an anal fissure. Be sure to tell them:

  • When you have pain, burning, or itching
  • How bad your discomfort is
  • How long the pain and discomfort usually lasts
  • What type of bleeding you've seen
  • What, if anything, improves your symptoms

Your doctor may ask about your diet, your bowel habits, and if you have any other medical conditions or intestinal problems.

Even though your doctor can usually diagnose an anal fissure from the symptoms you tell them, the best way to learn whether you have one is through a physical exam. Your doctor may look at the area for a fissure.

You probably won't need a rectal exam (when the doctor uses a gloved finger to feel inside the anus) or an anoscopy (when the doctor puts a lighted scope into the anal canal). Sometimes they're necessary, though.

Generally, a visual exam of the area is all it takes. But if your doctor thinks an inflammatory bowel disease has led to the anal fissure, you might need more tests. Often, the number and location of anal fissures can point to other conditions, like Crohn’s disease. The presence of a skin tag at one end of a fissure may also point to chronic anal fissures.

Your doctor might also suggest a test called a sigmoidoscopy to see the lower part of the colon, or the sigmoid colon. Or you may need a colonoscopy to look at the whole large intestine. Both tests involve inserting a long, thin, flexible, lighted tube into your anus to view the colon. They're used to look for abnormal growths or inflammatory conditions.

Once your doctor diagnoses an anal fissure, ask them these important questions:

  • Can I expect this fissure to heal on its own?
  • How can I treat an anal fissure at home?
  • Do I need medication?
  • Do I need to make changes to my diet?
  • How long should it take for the fissure to heal?
  • Am I likely to get more anal fissures?
  • Will I need surgery? What are the risks of surgery?

The goal of treatment is to relieve pain and discomfort, and heal the torn lining. Acute anal fissures -- the ones that don't last longer than 6 weeks -- are common and usually heal on their own with self-care. Chronic anal fissures -- those that last longer than 6 weeks -- may need medicine or surgery to help them heal.

If your fissures are caused by constipation or diarrhea, you can change a few habits to help lessen the strain on the anal canal. These steps can help relieve symptoms and encourage healing in most cases.

  • Stay hydrated. Drink plenty of caffeine-free fluids throughout the day. (Too much alcohol and caffeine can lead to dehydration.)
  • Eat a fiber-rich diet. To avoid constipation, your goal should be to get 20 to 35 grams of fiber every day. You can gradually increase the amount of fiber you eat by having more:
    • Wheat bran
    • Oat bran
    • Whole grains, including brown rice, oatmeal, and whole-grain pastas, cereals, and breads
    • Peas and beans
    • Citrus fruits
    • Prunes and prune juice
  • Try fiber supplements if you can’t get enough fiber from food. They can help soften stools and make you more regular. To avoid gas and cramping, gradually raise the amount of any fiber supplement you take until you reach the recommended dose.
  • Over-the-counter laxatives may help if adding more fiber to your diet does not. Before taking any laxatives, ask your doctor what they suggest.
  • Don't ignore your urge to go. Putting off bowel movements for later can lead to constipation; stools may become harder to pass and end up causing pain and tearing.
  • Don't strain or sit on the toilet too long. This can increase pressure in the anal canal.
  • Gently clean and dry your anal area after each bowel movement.
  • Avoid irritants to the skin, such as scented soaps or bubble baths.
  • Get treatment for chronic constipation or ongoing diarrhea.
  • Sitz baths, or hip baths, can promote healing of an anal fissure. By soaking the rectal area in a tub of warm water -- two or three times a day for 10 to 15 minutes -- you can clean the anus, improve blood flow, and relax the anal sphincter.

These habits are usually enough to heal most anal fissures within a few weeks to a few months. But when they aren't enough, ask your doctor about other treatments.

  • Nitrate ointment: Your doctor may prescribe one of these to help raise blood flow to the anal canal and sphincter, which helps fissures get better faster. Some side effects may include headaches, dizziness, and low blood pressure. Nitrate ointment should not be used within 24 hours of taking erectile dysfunction medicines like sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra).
  • Calcium channel blockers: These are blood pressure-lowering medications. Some of the topical ones can treat anal fissures, too. Side effects may include headaches.
  • Botox injections: When topical treatments don't work, injecting botulinum toxin type A (Botox) into the sphincter is sometimes the next step. Botox injections temporarily paralyze the sphincter muscle, relieving pain and encouraging healing in 60% to 80% of patients. You may not be able to control your bowel movements or passing gas, but it's temporary. The dose is extremely low, so there is no risk of botulism poisoning.

You probably won't need surgery for anal fissures unless other forms of treatment haven't worked. The surgery, called a lateral internal sphincterotomy (LIS), involves making a small cut in the anal sphincter muscle. It reduces pain and pressure, allowing the fissure to heal.

The pain from this surgery is usually mild. It hurts less than the fissure itself. The surgery might be followed by a temporary inability to control gas, mild fecal leakage, or infection. But in most cases, complete healing of fissures takes place within 8 weeks after surgery.

Show Sources

SOURCES:

American Society of Colon & Rectal Surgeons: "Anal Fissure," "Practice Parameters for the Management of Anal Fissures (3rd Revision)."

Cleveland Clinic: "Anal Fissures," "Fissure & Pruritus."

UpToDate: "Patient information: Anal fissure (Beyond the Basics)," "Patient information: High-fiber diet (Beyond the Basics)," "Patient information: Constipation in adults (Beyond the Basics)."

American Gastroenterological Association: "Medical position statement: Diagnosis and care of patients with anal fissure." 

Harvard School of Public Health, The Nutrition Source: "Fiber: Start Roughing It!"

American Heart Association: "Whole Grains and Fiber."

NHS Choices: "Anal Fissure - Prevention."

National Digestive Diseases Information Clearinghouse (NDDIC): "Flexible Sigmoidoscopy," "Colonoscopy."

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