American College of Gastroenterology
Advancing Gastroenterology, Improving Patient Care

Crohn’s Disease


If you have persistent symptoms such as diarrhea and abdominal pain or cramps, it could be Crohn’s disease. A chronic disorder, Crohn’s disease may cause you to have a wide-range of digestive symptoms that may be mild or severe and may flare up over time.

  • What is Crohn’s disease?

    Crohn’s disease belongs to a group of conditions known as inflammatory bowel disease (IBD). Crohn’s disease is a chronic disorder that can cause inflammation anywhere along the digestive tract from the mouth to the anus (end of the large intestine).

    Although Crohn’s disease usually occurs in the last part of the small intestine (called the ileum) and the beginning of the colon (the cecum i.e., the large intestine), it can develop in patches or involve anywhere along the digestive tract. The inflammation caused by Crohn’s disease can penetrate through the outer layer of the lining into deeper layers and even penetrate into adjacent organs. When this occurs, the “tunnel” that develops is called a fistula.

  • What is the outlook for people with Crohn’s disease?

    Although Crohn’s disease doesn’t have a cure, most people who have the disorder function well with proper treatment. The symptoms can come and go, with long periods of remission before symptoms flare up again, but it is important to know that many patients who have no symptoms still have active inflammation that may progress and cause bowel damage. Therefore, it is important to monitor the amount of inflammation in the bowel in order to manage the disease most effectively. For the best possible health and quality of life, visit your doctor regularly for checkups to monitor for symptoms and complications.

    Women who have Crohn’s disease can become pregnant and have healthy pregnancies, deliveries, and babies. Well-managed Crohn’s disease does not increase the risk of miscarriages, stillbirths, or congenital conditions.

    If you have Crohn’s disease and become pregnant, talk with your doctor. It is recommended that you speak with your gastroenterologist prior to becoming pregnant to avoid potential complications to you or your baby. The treatment goal during pregnancy is to prevent and treat flare-ups aggressively to minimize any risk to the unborn baby.

  • What are the signs and symptoms of Crohn’s disease?

    Signs and symptoms can range from mild to severe and vary depending on the part of the digestive tract affected. Symptoms usually develop over time but can occur suddenly.

    The most common symptoms of Crohn’s disease are:

    • Diarrhea
    • Pain and cramping in the abdomen (belly)
    • Fatigue
    • Feeling the need to have a bowel movement
    • Fever
    • Weight loss

    Other symptoms may include:

    • Blood in the stool
    • Drainage around the anus caused by inflammation
    • Joint pain
    • Loss of appetite
    • Nausea and vomiting
    • Pain, redness, or swelling in the eyes
    • Rashes
  • When should I see a doctor about Crohn’s disease?

    The signs and symptoms of Crohn’s disease can be similar to those of other conditions. If you have any symptoms, or changes in your bowel habits that persist, see your doctor for an evaluation.

  • What causes Crohn’s disease?

    Although medical experts don’t know the exact causes of Crohn’s disease, they think certain factors could be involved, such as:

    • Autoimmune response: A virus or bacterial infection might trigger Crohn’s disease, and an abnormal immune reaction causes the immune system to attack cells in the lining of the digestive tract.
    • Genes: People who have a family member with Crohn’s disease are more likely to develop the disease.
    • Environmental factors
  • What are the risk factors for Crohn’s disease?

    Risk factors for Crohn’s disease can include:

    • Age: Most people are diagnosed with the condition between ages 20 and 29, although it can occur at any age.
    • Family history: If you have one parent with Crohn’s disease, your lifetime risk of developing the disease is approximately 7 to 10 percent. If both parents have the disease, your lifetime risk increases to 35 percent.
    • Nonsteroidal anti-inflammatory drugs (NSAIDs): Medications such as ibuprofen, naproxen sodium, and others do not cause Crohn’s disease but can worsen inflammation and cause the disease to flare in people who already have the condition.
    • Race and ethnicity: White people and people of Eastern European Jewish (Ashkenazi Jewish) descent are at the highest risk.
    • Smoking: Tobacco use doubles the risk of Crohn’s disease and increases the likelihood of having a more severe form of the disease and requiring surgery.
    • Location: People who live in industrialized countries and urban areas are also at elevated risk of developing Crohn’s disease.
    • Antibiotics
    • Infections (GI)
  • Who should be evaluated for Crohn’s disease?

    See your doctor if you have any of the signs, symptoms, or risk factors for Crohn’s disease. Your doctor will perform an exam and testing to evaluate for the presence of other similar conditions or confirm a diagnosis.

  • How is Crohn’s disease diagnosed?

    Your doctor will discuss your symptoms, medical history and risk factors for Crohn’s disease and conduct a physical exam to check for signs of the condition. Although no single test for Crohn’s disease exists, a combination of tests can rule out other conditions and confirm a diagnosis.

    Tests that you may need:

    • Blood tests to check for signs of infection, anemia (low blood count), malabsorption and abnormal liver tests.
    • Stool sample to check for blood in the stool and for infections that can simulate active IBD
    • CT or MRI scans to provide highly detailed images for closer evaluation

    Doctors may also use diagnostic procedures such as:

    • Colonoscopy or flexible sigmoidoscopy: Using a thin, flexible scope with a lighted camera, your doctor examines the inside of the colon and possibly the lower end of the small intestine (colonoscopy).
    • Biopsy: Your doctor may perform this procedure during a colonoscopy, taking a small tissue sample for evaluation under a microscope.
    • Upper endoscopy: Also called an esophagogastroduodenoscopy (EGD), this procedure examines the upper part of the digestive tract.
    • Capsule endoscopy: You swallow a capsule containing a tiny camera that takes pictures of the digestive tract and transmits the images to a computer for your doctor to examine.
    • CT scans or MRI imaging: these imaging tests may be used to better characterize the amount of small intestine or other parts of the abdominal organs that may be inflamed
    • Barium x-rays: although not used as often any more, this test involves drinking a liquid or having it administered by enema that will allow x-rays to show how the bowel is shaped and looks.
  • What are the treatments for Crohn’s disease?

    Currently, there is no cure for Crohn’s disease, and treatments work differently in different people. The goal of treatment is to relieve symptoms, heal the inflammation within the bowel, prevent complications, and improve your quality of life.

    Doctors typically begin your treatment plan with medications to bring symptoms under control. Then you receive treatment aimed at maintaining remission and reducing the frequency of flare-ups.


    Your doctor may use one or more medications such as:

    • Antibiotics: These medications can reduce drainage and heal abscesses. They may also help reduce harmful bacteria in the intestines that might be stimulating the immune system.
    • Steroids: Corticosteroids can reduce inflammation throughout the body by suppressing the entire immune system. There is also a steroid called budesonide that works primarily in the bowel and does not affect the rest of the immune system.
    • Immunosuppressant medications: These medications reduce the body’s immune response to reduce inflammation and allow the intestinal tissue to heal.
    • Biologic therapies: These medications block the body’s immune response. Doctors typically use biologic therapies to treat moderate to severe Crohn’s disease.

    Nutrition therapy

    • In children, specialized liquid diets have been shown to have some benefit in treating Crohn’s disease, but these are difficult to tolerate so are usually administered through a tube. This approach to management is not sustainable for most people.
    • Some patients with Crohn’s disease may need temporary intravenous nutrition (fluid nutrition injected through a vein) and bowel rest. This is reserved for more severe cases.


    If other treatments do not effectively relieve your symptoms, or if disease-related complications present (such as a stricture [narrowing of the bowel] or a precancer or cancer arises in the bowel), surgery can provide a temporary solution. Surgery does not cure Crohn’s disease. The surgeon removes the damaged/abnormal portions of the digestive tract and reconnects the healthy sections. About half of the people with Crohn’s disease need surgery to control symptoms over the course of their lifetime.

    Alternative medicine

    Complementary and alternative medicine (CAM) therapies, such as acupuncture, fish oil, or nutritional supplements, have not shown significant benefit for treating Crohn’s disease.

  • Am I at risk of developing other conditions?

    People with Crohn’s disease can develop complications related to the condition or may experience side effects from their medications. Some common complications include:

    • Anal fissures: A tear in the tissue lining the anus or in the skin around the anus, which can cause painful bowel movements, blood in the stool, and sometimes localized itching of the anus.
    • Ulcers: These open sores in the digestive tract, including the mouth, genital area and anus, can result from chronic inflammation.
    • Fistulas: If ulcers extend through the intestinal wall, an abnormal tunnel between different areas can develop. Fistulas can lead to drainage, infections, and diversion of food, which can prevent you from getting enough nutrients.
    • Bowel obstruction: Long-term inflammation can cause scar tissue to form, which can thicken and narrow areas of the bowel, blocking the flow of digestive contents. Medications can reduce inflammation and open up the narrowed areas, but some people require surgery to remove the diseased portion of the bowel.
    • Malnutrition: Symptoms of Crohn’s disease, such as diarrhea, abdominal pain, and abdominal cramping, may make eating difficult. Intestinal inflammation can prevent proper absorption of vital nutrients needed to maintain a state of good health.
    • Colon cancer: Crohn’s disease that affects the colon increases the risk of developing colon cancer. People with Crohn’s disease should have colonoscopies more frequently than people without risk factors. In certain situations, your physician may want to spray a dye in the bowel (this is called “chromoendoscopy”) during your colonoscopy to better see lesions.
  • What are some recommendations for living with Crohn’s disease?

    If you have Crohn’s disease, healthy lifestyle habits can help you maintain a good quality of life. Talk to your doctor about:

    • Healthy eating plan: Certain changes can help reduce symptoms, but it’s important to understand that symptom management does not mean that the inflammation is under control. A healthy eating plan should be accompanied by appropriate measures to make sure it is nutritious (that you are receiving the nutrition you need), and that your inflammation is being measured and monitored to make sure the treatments are achieving their goals:
      • Eat nutritious foods
      • Drink more liquids
      • Avoid carbonated (fizzy) drinks
      • Avoid excessive high-fiber foods such as popcorn, vegetable skins, or nuts
      • Avoid fatty, fried foods, or fast foods.
      • Take vitamins (such as vitamin D or vitamin B12) or other nutritional supplements, if recommended by your doctor
    • Exercise: Make time for regular physical activity each day. Exercise can be as simple as walking for 10 to 20 minutes per day and can help relieve stress and minimize symptoms.
    • Smoking cessation: Quitting smoking reduces your risk of health complications due to Crohn’s disease.

Author(s) and Publication Date(s)

Joseph Feuerstein, MD, Beth Israel Deaconess, Boston, MA– Updated April 2021.

Reviewed by Gary R. Lichtenstein, MD, FACG, University of Pennsylvania and David T. Rubin, MD, FACG, University of Chicago – June 2019.

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