Crohn’s Disease

Crohn’s disease is a form of inflammatory bowel disease. It usually affects the intestines, but may occur anywhere from the mouth to the end of the rectum (anus).


The two most common types of inflammatory bowel disease are ulcerative colitis and Crohn’s disease. Together, they afflict an estimated two million people in the U.S. Both diseases cause inflammation and ulcers. Crohn’s disease symptoms most commonly affect the last portion of the small intestine (called the ileum) and/or the large intestine (colon and rectum).

Alternate names

Inflammatory bowel disease: Crohn’s disease, regional enteritis, ileitis, granulomatous ileocolitis

Causes, incidence and risk factors

The exact cause of Crohn’s disease is unknown. It is an autoimmune disorder, a condition that occurs when your body’s immune system mistakenly attacks and destroys healthy body tissue.

People with Crohn’s disease have ongoing, or chronic, inflammation of the gastrointestinal tract. Crohn’s disease may involve the small intestine, the large intestine, the rectum or the mouth. The inflammation causes the intestinal wall to become thick.

There are different types of Crohn’s disease. The type depends on what part of your body is affected.

The following seem to play a role in Crohn’s disease:

  •   Genetics
  •   Environmental factors
  •   The body over-reacts to normal bacteria in the intestines

Crohn’s disease may occur at any age but commonly occurs in people between ages 15-35.

You are more likely to get this disease if you:

Signs and symptoms

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

The main symptoms of Crohn’s disease are:

Other symptoms may include:

  •     Constipation
  •     Eye inflammation
  •     Fistulas (usually around the rectal area, may cause draining of pus, mucus or stools)
  •     Joint pain and swelling
  •     Mouth ulcers
  •     Rectal bleeding and bloody stools
  •     Skin lumps or sores (ulcers)
  •     Swollen gums


A physical examination may reveal an abdominal mass or tenderness, skin rash, swollen joints or mouth ulcers. Tests to diagnose Crohn’s disease include:

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:


Ulcerative colitis is a chronic condition that can be medically treated to keep it in remission. Remission is a period of time in which a person experiences no symptoms of the disease.

If you have Crohn’s disease, your doctor likely will prescribe medicines and recommend dietary and lifestyle changes as the first treatment steps.

Diet and Nutrition

You should eat a well-balanced, healthy diet. It is important to get enough calories, protein and essential nutrients from a variety of food groups. No specific diet has been shown to make Crohn’s symptoms better or worse. Specific food problems may vary from person to person.

However, certain types of 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:

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


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

Ask your doctor or nurse for tips on how to manage your stress.


You can take medication to treat very bad diarrhea. Loperamide (Imodium) can be bought without a prescription. Always talk to your doctor or nurse 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) without a prescription. Ask your doctor about these products.
  • Always talk to your doctor before using any laxative medicines.
  • You may use acetaminophen (Tylenol) for mild pain.
  • Drugs such as aspirin, ibuprofen (Advil, Motrin) or naproxen (Aleve, Naprosyn) may make your symptoms worse.

Your doctor may also give you a prescription for stronger pain medicines.

Medicines that may be prescribed include:

  •    Aminosalicylates (5-ASAs) are medicines that help control mild to moderate symptoms. Some forms of the drug are taken by mouth; others must be given rectally.
  •    Corticosteroids (prednisone and methylprednisolone) are used to treat moderate to severe Crohn’s disease. They may be taken by mouth or inserted into the rectum.
  •    Medicines such as azathioprine or 6-mercaptopurine quiet the immune system’s reaction.
  •    Antibiotics may be prescribed for abscesses or fistulas.
  •    Biologic therapy is used to treat patients with severe Crohn’s disease that does not respond to any  other types of medication. Medicines in this group include Infliximab (Remicade) and adalimumab (Humira), certolizumab (Cimzia), and natalizumab (Tysabri).


If these measures prove over a prolonged period of time to be ineffective in managing your condition, you may need surgery to remove all or part of the diseased intestine(s). Surgery is a helpful option especially if you have complications of Crohn’s disease, such as:

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

UF Health surgeons strive to leave as much of a patient’s colon and bowel intact as possible.

Some patients may need surgery to remove the entire large intestine (colon), with or without the rectum.

A type of surgery called bowel resection may be needed to remove a damaged or diseased part of the intestine or to drain an abscess. However, removing the diseased portion of the intestine does not cure the condition.

Strictureplasty is a technique which lets a surgeon widen a portion of the bowel that has become narrow due to the damage and scarring caused by Crohn’s disease.

Surgical treatment of these diseases often relieves symptoms long-term and frequently limits or eliminates the need for ongoing use of prescribed medications.

See also:

Expectations (prognosis)

There is no cure for Crohn’s disease. The condition is marked by periods of improvement followed by flare-ups of symptoms.

Support groups

The Crohn’s and Colitis Foundation of America offers support groups throughout the United States. It is very important to stay on medications long-term to try to keep the disease symptoms from returning. If you stop or change your medications for any reason, let your doctor know right away. You have a higher risk for small bowel and colon cancer if you have Crohn’s disease.


  •   Abscess
  •   Bowel obstructions
  •   Complications of corticosteroid therapy, such as thinning of the bones
  •   Erythema nodosum
  •   Fistulas in the bladder, skin or vagina
  •  Inflammation of the joints
  •  Impaired growth and sexual development in children
  •  Lesions in the eye
  •  Narrowing (strictures) of the intestine
  •   Nutritional deficiency (particularly vitamin B12 deficiency)
  •   Pyoderma gangrenosum

When to call your health care provider

Call for an appointment with 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 without an illness
  •   You have nausea and vomiting that lasts for more than a day
  •   You have skin sores or lesions that do not heal
  •   You have joint pain that prevents you from doing your everyday activities
  •   You have side effects from any drugs prescribed for your condition


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.

Fry RD, Mahmoud N, Maron DJ, Ross HM, Rombeau J. Colon and rectum. In: Townsend CM, Beauchamp RD, Evers BM, Mattox KL, eds. Sabiston Textbook of Surgery. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 50.

Sands BE, Siegel CA. Crohn’s disease. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran’s Gastrointestinal and Liver Disease. 9th ed. Philadelphia, Pa: Saunders Elsevier;2010:chap 111.

Content Reviewers

David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc., and George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. 10/16/11

Sanda Tan, MD, PhD, UF colorectal surgeon, August 2013