What Is Crohn’s Disease?

Crohn’s disease is a chronic inflammatory bowel condition that results in inflammation of the gastrointestinal tract. Crohn’s disease can affect any part of the gastrointestinal tract; however, it most commonly affects the lower small intestine (ileum) or the beginning of the large intestine (colon).

The symptoms of Crohn’s disease vary greatly among patients depending on the severity and location of the inflammation. However, patients with Crohn’s disease commonly experience the following symptoms:

Furthermore, they may experience other general signs and symptoms including nausea, loss of appetite, tiredness, and anemia (decreased red blood cell count). On occasion, patients may present with signs and symptoms including joint pain and swelling, eye irritation, and skin changes (red, tender bumps under the skin). These occasional symptoms suggest that inflammation is present outside of the intestines.

Crohn’s disease usually begins gradually and progressively worsens over time. Many individuals have periods of remission, lasting from weeks to years where their symptoms disappear.

Complications of Crohn’s disease can include bowel obstruction, anal fissures, fistulas, ulcers, malnutrition, and inflammation in other areas of the body (i.e. skin, joints, and eyes). Furthermore, the risk of developing colon cancer may be higher in individuals who have Crohn’s disease in the large intestine. These patients should discuss screening regimens for colon cancer, including colonoscopy with biopsies. Screening can help to diagnose colon cancer at an earlier stage, improving the chance for recovery.

Diagnosis of Crohn’s disease may include a detailed medical history (including family history), thorough physical examination, laboratory tests, upper GI series (barium swallow), computed tomography (CT) scan, or intestinal endoscopy. Intestinal endoscopy includes upper GI endoscopy and enteroscopy, capsule endoscopy, and colonoscopy. These are the most accurate tests to diagnose Crohn’s disease and rule out alternative conditions, such as cancer, diverticular disease, or ulcerative colitis.

What Causes Crohn’s Disease?

The exact cause of Crohn’s disease remains unknown; however, researchers believe that a number of factors may play a role in the development of Crohn’s disease, including:

  • Autoimmune reactions: This occurs when the body mistakenly attacks healthy cells in the body. Researchers suggest that viruses or bacteria can trigger the immune system to mistakenly attack the inner lining of the intestines, causing inflammation and leading to symptoms of Crohn’s disease.
  • Genes: Crohn’s disease is occasionally seen in family members. Research has demonstrated that individuals with a parent or sibling with Crohn’s disease may be more likely to develop the disease.
  • Environmental issues: Some research has suggested that certain factors in the environment may increase an individual’s risk of developing Crohn’s disease. Use of antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), and oral contraceptives may increase the risk of developing the disease. Additionally, consuming a diet high in fat may slightly increase an individual’s risk of developing Crohn’s disease.

Certain factors have been identified that increase an individual’s risk of developing Crohn’s disease, including:

  • Age: Individuals between the ages of 20 and 29 are more commonly affected
  • Genetics: Individuals with a parent or sibling who have Crohn’s disease are more commonly affected
  • Smoking status: Individuals who smoke are more commonly affected

Treatments For Crohn’s Disease

Treatment of Crohn’s disease depends on the severity of the disease and the symptoms that an individual is experiencing. Generally, Crohn’s disease is treated with medications, bowel rest, or surgery, in addition to diet modifications.

From a pharmacological standpoint, while no medications have been developed to cure Crohn’s disease, treatment with medication can help to induce and maintain remission and improve an individual’s quality of life. Many patients with Crohn’s disease are prescribed medications depending on their symptoms.

Pharmacologic options that are commonly prescribed include:

  • Aminosalicylates: Includes balsalazide, mesalamine, olsalazine, and sulfasalazine. These medications help to control inflammation. These are often used to treat patients that suffer from mild symptoms.
  • Corticosteroids: Includes budesonide, hydrocortisone, prednisone, and methylprednisone. These medications help to suppress immune system activity and reduce inflammation. These are often used to treat patients who suffer from moderate to severe symptoms.
  • Immunomodulators: Includes 6-mercaptopurine, azathioprine, cyclosporine, and methotrexate. These medications help to reduce immune system activity, and decrease inflammation. These medications can take up to three months to start working. These medications are often used to help patients go into remission or to help patients who are non-responsive to other treatment options. Cyclosporine is only prescribed to patients with severe symptoms as the medication has serious side effects.
  • Biologic therapies: Includes adalimumab, certolizumab, infliximab, natalizuab, and vedolizumab. These medications neutralize a targeted protein in the immune system, which helps to decrease inflammation in the intestine. Biologic therapies exert their effects quickly and help to bring on remission, most notably in patients who do not respond to other treatment options.

Some patients may be prescribed additional medication to help manage their symptoms or complications of the disease. Acetaminophen is often used to treat mild pain (patients with Crohn’s disease should avoid ibuprofen, aspirin, and naproxen as these medications may worsen their symptoms). Antibiotics are used to prevent and treat fistulas and infections. Loperamide may be used for short periods of time to slow or stop diarrhea (this drug is not recommended for long-term use as it can increase the risk of developing megacolon).

Bowel rest is often recommended for patients with severe symptoms. Bowel rest may be for a period of a few days or may last several weeks. It involves only drinking clear fluids and having no oral intake. In order to provide proper nutrition for patients on bowel rest, IV nutrition is delivered via a catheter (or tube) into the arm. Some patients on bowel rest are treated in the hospital, while others receive treatment at home. The majority of patients are able to heal their intestines with bowel rest.

Up to 20% of patients with Crohn’s disease will require surgery to treat their disease, even with medication and bowel rest. Surgery will not cure Crohn’s disease, but it does treat associated complications and can help to improve symptoms. Surgery is often recommended to treat life threatening bleeding, fistulas, bowel obstructions, life threatening side effects of medications, and severe symptoms that are non-responsive to medications.

Surgeries that may be performed on patients with Crohn’s disease include small bowel resection, subtotal colectomy, and proctocolectomy and ileostomy. Patients requiring surgery are often admitted to the hospital for three to seven days and full recovery usually takes four to six weeks.

Patients suffering with Crohn’s disease can also make dietary changes to help manage their condition, including:

  • Avoiding carbonated drinks
  • Drinking more liquids
  • Eating more frequent and smaller meals
  • Avoiding high fiber foods
  • Keeping a food diary to identify food triggers

Additionally, nutritional supplements may be utilized for individuals who do not absorb sufficient vitamins and nutrients from the food that they consume. Patients with Crohn’s disease are advised to consult with a healthcare practitioner to identify specific dietary recommendations for their case.


Crohn’s disease is a chronic inflammatory bowel condition that leads to inflammation of the gastrointestinal tract. Common symptoms of the disease include diarrhea, abdominal pain and cramping, and weight loss. Some patients may experience other symptoms as well, including nausea, tiredness, and anemia.

Treatment of Crohn’s disease may involve medications, bowel rest, and potentially surgery. Further, patients with Crohn’s disease should make dietary changes to help manage their symptoms. Individuals experiencing symptoms of Crohn’s disease are encouraged to speak to their physician to help diagnose and treat this inflammatory condition.


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