Medically Reviewed by Matthew Hamilton, MD

Crohn’s disease (CD) can trigger inflammation anywhere in your gastrointestinal tract, including the region around your anus. Sometimes, this inflammation leads to anal fissures, centimeter-sized tears or cracks in the area’s thin lining, called the mucosa.

“The problems involving fissures in Crohn’s disease are some of the more devastating, because it can be extremely uncomfortable,” says David Binion, MD, a gastroenterologist and co-director of the Inflammatory Bowel Disease Center at the University of Pittsburgh Medical Center in Pennsylvania. Anal fissures can bleed and be intensely painful, he explains, and may lead to potentially dangerous medical issues, like abscesses and fistulas.

Fortunately, fissures don’t often get that far. Here’s the lowdown on these small lesions, including their characteristics, symptoms, and treatment.

Regular Anal Fissures vs. Crohn’s Anal Fissures

Anal fissures are common among both children and adults, with and without CD. They can develop for a variety of reasons, including physical trauma, and certain rare infections and diseases. In those without CD, they’re most often the result of constipation or diarrhea.

“Normal people who struggle with constipation and pass really hard stool can sometimes cause little breaks, just from pressure,” says Byron Vaughn, MD, a gastroenterologist and assistant professor of medicine at University of Minnesota Medical School in Minneapolis. “At the same time people who have a lot of diarrhea—sometimes that wear and tear can break down the skin there.”

While people with CD frequently have these issues, which can irritate the mucosa, the development of their anal fissures most often occurs when the CD is active in the setting of inflammation. Compared to people without the disease, Crohn’s patients are also more likely to have multiple anal fissures. They tend to be located in slightly different areas around the anus, as well—along the sides, for example, rather than down the middle.

What It Feels Like to Have an Anal Fissure

Though many CD patients won’t develop any symptoms, anal fissures can be very painful during and after bowel movements. “It’s like having a little cut in your anus,” explains Dr. Vaughn. “So every time they’re physically having stool or diarrhea moves across their anus, they’re having pain.”

“It’s so painful that it can actually trigger a fear of passing stool,” explains Manreet Kaur, MD, a gastroenterologist and the medical director of the Inflammatory Bowel Disease Center at Baylor College of Medicine in Houston, Texas. As a result, patients may postpone their bowel movements. “The longer you do that, the harder the stool gets,” she says. “It’s a vicious cycle.”

Another possible symptom of fissures: bleeding. “It’s usually not a significant amount,” says Dr. Kaur. “It’s usually bright red blood either on the outside of the stool, or on the toilet paper when you wipe.”

It is important to note that if you experience pain or see blood, visit your healthcare provider (HCP). They will note your symptoms and conduct a physical exam to confirm it’s a fissure, and assess for other possible complications of CD. Starting treatment early can alleviate symptoms faster and allow the fissure to heal. Sometimes, a fissure may lead to a fistula—an abnormal connection that forms between two body parts—or a pocket of infection called an abscess.

The good news, says Vaughn, is fissures don’t usually progress, partly since “they’re diagnosed so quickly because they’re so painful.”

scalpel and medical chart depicting diagnosis of anal fissure for patient with Crohn's disease

Treating an Anal Fissure

Research suggests about four in five CD-related anal fissures heal by themselves. In the meantime, experts recommend sitz baths, during which you submerge your buttocks and hips in water. “They can help relax the area, clean it out a little bit and help with some of that burning sensation,” says Vaughn. Topical pain relievers like lidocaine may also help; ask your HCP which ones could work for you.

Getting a handle on diarrhea or constipation is also key. For constipation, your HCP may recommend additional fluids, more fiber or a stool softener. For diarrhea, says Vaughn, “You really want to work on forming the stool.” Increasing fiber may be in order, but he cautions that high-fiber diets may worsen bloating and diarrhea during a flare. Again, consult your HCP for guidance.

If your fissure doesn’t improve by itself, the next step is medical treatment. To better your chances of healing, your HCP will prescribe drugs to relax the anal sphincter muscles, which can relieve pressure, help improve blood flow, and alleviate pain. A topical nitroglycerin ointment or calcium channel blocker, such as nifedipine, are effective first-line options. Occasionally, botulinum toxin (BOTOX) may be used.

Surgery is needed for a minority of CD-related fissures. A surgeon may perform what is called a lateral internal sphincterotomy where they make a small cut to the internal anal sphincter to ease pressure on the fissure.

Preventing Future Fissures

Crohn’s patients can best facilitate fissure recovery and prevention by addressing their underlying disease, says Kaur. Even if you don’t have evident symptoms, following your treatment plan is critical. Good-for-you habits like eating a healthy diet, avoiding tobacco, and getting enough sleep can also help.

“We always encourage our patients to take good care of themselves,” says Dr. Binion, “and to have a good relationship with their healthcare providers so that they can identify problems quickly and early, so they don’t become complications.”


Kristen Sturt is a New Jersey-based writer specializing in health and wellness. Previously, she was an editor at Sharecare and Grandparents.com (now Considerable.com), as well as a longtime writer at VH1. For kicks, she cooks, travels and spends time with her husband and two children.

Medical reviewer and Oshi physician-partner Matthew J. Hamilton, MD is an Assistant Professor of Medicine at Harvard Medical School and a specialist in Gastroenterology, Hepatology, and Endoscopy at Brigham and Women’s Hospital Crohn’s and Colitis Center in Boston. He is a leading member of the research team at the BWH Crohn’s and Colitis Center, and has garnered national recognition for his research into the underlying inflammatory processes of IBD.

Oshi is a tracking tool and content resource. It does not render medical advice or services, and it is not intended to diagnose, treat, cure, or prevent any disease. You should always review this information with your healthcare professionals.