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Crohn disease


Crohn disease is a disease where parts of the digestive tract become inflamed.

  • It most often involves the lower end of the small intestines and the beginning of the large intestine.
  • It may also occur in any part of the digestive system from the mouth to the end of the rectum (anus).

Crohn disease is a form of inflammatory bowel disease (IBD).

Ulcerative colitis is a related condition.

Alternative Names

Crohn's disease; Inflammatory bowel disease - Crohn's disease; Regional enteritis; Ileitis; Granulomatous ileocolitis; IBD- Crohn's disease


The exact cause of Crohn disease is unknown. It occurs when your body's immune system mistakenly attacks and destroys healthy body tissue (autoimmune disorder).

When parts of the digestive tract remain swollen or inflamed, the walls of the intestines become thickened.

Factors that may play a role in Crohn disease include:

  • Your genes and family history (People of Jewish descent are at higher risk.)
  • Environmental factors
  • Tendency of your body to over-react to normal bacteria in the intestines
  • Smoking

Crohn disease may occur at any age. It most often occurs in people between ages 15 to 35.


Symptoms depend on what part of the digestive tract is involved. Symptoms range from mild to severe, and can come and go with periods of flare-ups.

The main symptoms of Crohn disease are:

  • Crampy pain in the abdomen (belly area)
  • Fever
  • Fatigue
  • Loss of appetite
  • Feeling that you need to pass stools, even though your bowels are already empty. It may involve straining, pain, and cramping.
  • Watery diarrhea, which may be bloody
  • Weight loss

Other symptoms may include:

  • Constipation
  • Sores or swelling in the eyes
  • Draining of pus, mucus, or stools from around the rectum or anus (caused by something called a fistula)
  • Joint pain and swelling
  • Mouth ulcers
  • Rectal bleeding and bloody stools
  • Swollen gums
  • Tender, red bumps (nodules) under the skin which may turn into skin ulcers

Exams and Tests

A physical exam may show a mass or tenderness in the abdomen, skin rash, swollen joints, or mouth ulcers.

Tests to diagnose Crohn disease include:

  • Barium enema or upper GI series
  • Colonoscopy or sigmoidoscopy
  • CT scan of the abdomen
  • Capsule endoscopy
  • MRI of the abdomen
  • Enteroscopy

A stool culture may be done to rule out other possible causes of the symptoms.

This disease may also alter the results of the following tests:

  • Low albumin levels
  • High sed rate
  • Fecal fat
  • Low blood count (hemoglobin and hematocrit)
  • Abnormal liver blood tests
  • High white blood cell count


Managing Crohn disease at home:


You should eat a well-balanced, healthy diet. Include enough calories, protein, and nutrients from a variety of food groups.

No specific diet has been shown to make Crohn symptoms better or worse. Types of food problems may vary from person to person.

Some foods can make diarrhea and gas worse. To help ease symptoms, try:

  • Eating small amounts of food throughout the day.
  • Drinking lots of water (drink small amounts often throughout the day).
  • Avoiding high-fiber foods (bran, beans, nuts, seeds, and popcorn).
  • Avoiding fatty, greasy or fried foods and sauces (butter, margarine, and heavy cream).
  • Limiting dairy products if you have problems digesting dairy fats. Try low-lactose cheeses, such as Swiss and cheddar, and an enzyme product, such as Lactaid, to help break down lactose.
  • Avoiding foods that you know cause gas, such as beans.

Ask your doctor about extra vitamins and minerals you may need, such as:

  • Iron supplements (if you are anemic)
  • Calcium and vitamin D supplements to help keep your bones strong
  • Vitamin B12 to prevent anemia

If you have an ileostomy, you will need to learn:


You may feel worried, embarrassed, or even sad and depressed about having a bowel disease. Other stressful events in your life, such as moving, a job loss, or the loss of a loved one can worsen digestive problems.

Ask your health care provider for tips on how to manage your stress.


You can take medicine to treat very bad diarrhea. Loperamide (Imodium) can be bought without a prescription. Always talk to your provider before using these drugs.

Other medicines to help with symptoms include:

  • Fiber supplements may help your symptoms. You can buy psyllium powder (Metamucil) or methylcellulose (Citrucel). Ask your doctor before taking these products or laxatives.
  • Acetaminophen (Tylenol) for mild pain. Avoid drugs such as aspirin, ibuprofen (Advil, Motrin), or naproxen (Aleve, Naprosyn) which can make your symptoms worse.

Your doctor may also prescribe medicines to help control Crohn disease:

  • Aminosalicylates (5-ASAs), medicines that help control mild to moderate symptoms. Some forms of the drug are taken by mouth; others must be given rectally.
  • Corticosteroids, such as prednisone, treat moderate to severe Crohn disease. They may be taken by mouth or inserted into the rectum.
  • Medicines that quiet the immune system's reaction.
  • Antibiotics, treat abscesses or fistulas.
  • Biologic therapy, used for severe Crohn disease that does not respond to any other types of medicines.


Some people with Crohn disease may need surgery to remove a damaged or diseased part of the intestine. In some cases, the entire large intestine is removed, with or without the rectum.

People who have Crohn disease that does not respond to medicines may need surgery to treat problems such as:

  • Bleeding
  • Failure to grow (in children)
  • Fistulas (abnormal connections between the intestines and another area of the body)
  • Infections
  • Narrowing of the intestine

Surgeries that may be done include:

Support Groups

The Crohn's and Colitis Foundation of American offers support groups throughout the United States.

Outlook (Prognosis)

There is no cure for Crohn disease. The condition is marked by periods of improvement followed by flare-ups of symptoms. Although Crohn disease cannot be cured even with surgery, treatment can offer significant help to most people.

Possible Complications

You have a higher risk for small bowel and colon cancer if you have Crohn disease. At some point, your doctor may recommend tests to screen for colon cancer.

Those with more severe Crohn disease may have these problems:

  • Abscess or infection in the intestines
  • Anemia, a lack of red blood cells
  • Bowel blockage
  • Fistulas in the bladder, skin, or vagina
  • Slow growth and sexual development in children
  • Swelling of the joints
  • Lack of important nutrients, such as vitamin B12 and iron
  • Problems with maintaining a healthy weight

When to Contact a Medical Professional

Call your health care provider if:

  • You have very bad abdominal pain.
  • You cannot control your diarrhea with diet changes and drugs.
  • You have lost weight, or a child is not gaining weight.
  • You have rectal bleeding, drainage, or sores.
  • You have a fever that lasts for more than 2 or 3 days, or a fever higher than 100.4°F (38°C) without an illness.
  • You have nausea and vomiting that lasts for more than a day.
  • You have skin sores that do not heal.
  • You have joint pain that prevents you from doing your everyday activities.
  • You have side effects from medicines you are taking for your condition.


Cheifetz AS. Management of active Crohn disease. JAMA. 2013 May 22;309(20):2150-8. PMID: 23695484

Fry RD, Mahmoud NN, Maron DJ,, Bleier JIS. Colon and rectum In: Townsend CM Jr, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 19th ed. Philadelphia, PA: Elsevier Saunders; 2012:chap 52.

Lichenstein GR. Inflammatory bowel disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 143.

Lichtenstein GR, Hanauer SB, Sandborn WJ; Practice Parameters Committee of American College of Gastroenterology. Management of Crohn's disease in adults. Am J Gastroenterol. 2009;104(2):465-483. PMID: 19174807

Sandborn WJ. Crohn's disease evaluation and treatment: clinical decision tool. Gastroenterology. 2014;147(3):702-5. PMID: 25046160

Terdiman JP, Gruss CB, Heidelbaugh JJ, Sultan S, Falck-Ytter YT, et al. American Gastroenterological Association Institute Guideline on the Use of Thiopurines, Methotrexate, and Anti-TNF-a Biologic Drugs for the Induction and Maintenance of Remission in Inflammatory Crohn's Disease. Gastroenterology. 2013;145(6):1459-63. PMID: 24267474

Review Date: 1/22/2015
Reviewed By: Subodh K. Lal, MD, gastroenterologist at Gastrointestinal Specialists of Georgia, Austell, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
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