What Is Crohn's Disease?

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Crohn's disease is a chronic, incurable disease that can cause inflammation anywhere along the digestive tract. Along with ulcerative colitis, it is one of two gastrointestinal disorders classified as an inflammatory bowel disease (IBD). Crohn's disease is characterized by symptoms of diarrhea, abdominal pain, cramping, bloating, weight loss, and blood in stools.

Crohn's disease can be a frustrating condition since there is no clear cause. Colonoscopy with biopsy is currently the most effective means of diagnosis. Treatment is focused primarily on the management of symptoms and may include antibiotics, corticosteroids, and immune-modifying drugs. Surgery may be needed in cases of intestinal rupture or bowel obstruction.

Coping with Crohn's Disease
 Verywell / Ellen Lindner

Types of Crohn's Disease

Crohn's disease affects people differently, mainly because of the variety of types and the areas they affect. The most common types of Crohn's disease are:

  • Ileocolitis (affecting the colon and adjacent ileum)
  • Ileitis (affecting just the ileum)
  • Crohn's granulomatous colitis (affecting just the colon)
  • Gastroduodenal Crohn's disease (affecting the stomach and adjacent duodenum)
  • Jejunoileitis (affecting the jejunum)

Crohn's Disease Symptoms

Crohn's disease is characterized by inflammation that, while centered on the gastrointestinal tract, can affect other organs.

Symptoms of Crohn's disease vary by the location of inflammation or injury.

Symptoms tend to develop over the course of years and are usually more subtle than ulcerative colitis, especially in the early stages.

The most common signs and symptoms include:

  • Abdominal pain
  • Cramping
  • Diarrhea
  • Fever
  • Blood in stool
  • Loss of appetite
  • Weight loss

Crohn’s disease is a progressive illness in which persistent inflammation can trigger profound changes in the structure of the gastrointestinal tract. This can often lead to a narrowing of the intestinal passage (strictures) and the development of abscesses, fissures, and fistulas.

Serious complications include bowel obstruction, bowel perforation, and toxic megacolon (a potentially life-threatening condition in which the colon loses the ability to contract).

Colorectal cancer occurs four times more frequently in people with Crohn's disease than in the general public.

Long-term inflammation can affect multiple organs, potentially causing issues such as central vision loss, arthritis, osteoporosis, gallstones, and other concerns.

While most extraintestinal symptoms of Crohn's disease usually develop after the intestinal ones, they can sometimes be the first signs of the disease.


While the exact cause of Crohn's disease is unknown, it is believed to be associated with a combination of genetic and environmental factors.

Crohn’s disease was once believed to be an autoimmune disorder, but most research today suggests that it is caused by a failure of your innate immunity. This is the part of your immune system that launches the frontline assault on disease and helps regulate the balance of bacteria in your gastrointestinal tract.

If your innate immune defenses fail to work as they're supposed to, harmful bacteria can overgrow and cause harm.


Diagnosing Crohn’s disease can be tricky. Even with multiple forms of testing, the disease can often be difficult to pin down with any certainty.

Direct visualization is considered the cornerstone of the investigation. It involves a procedure known as endoscopy in which a flexible lighted scope is inserted into either your rectum or throat to look for evidence of gastrointestinal inflammation and tissue damage (often described as having a "cobblestone-like" appearance).

Colonoscopy is the most common endoscopic procedure used to diagnose Crohn's disease, though sigmoidoscopy or upper endoscopy may be used in some cases. 

Indirect visualization is used when endoscopy cannot offer definitive evidence of the disease and may involve X-rays, computed tomography (CT), magnetic resonance imagining (MRI), or ultrasound.

Blood tests cannot diagnose Crohn’s disease but can help identify and measure the effect of the disease on the body. Complete blood count (CBC)erythrocyte sedimentation rate (ESR)C-reactive protein (CRP), and antibody tests may be used. Other blood tests may be done to determine whether there are any deficiencies in sodium, potassium, and other electrolytes lost through chronic diarrhea.


Crohn's disease can be treated with diet, bowel rest, medications, and surgery.

While there is an ever-widening range of tools able to achieve disease remission, it may take several attempts to find the treatment that's right for you.

It is important to have patience and to work with a board-certified gastroenterologist experienced with IBD.

Crohn's Disease Doctor Discussion Guide

Get our printable guide for your next doctor's appointment to help you ask the right questions.

A treatment plan may involve:

  • Diet: While there is no "Crohn’s diet," per se, a tailored dietary plan can help you maintain optimal nutrition while placing less stress on your digestive tract. This typically involves a high-calorie, high-protein diet to compensate for the malabsorption of nutrients common with Crohn’s disease; increased intake of soluble fiber to ensure bowel regularity and reduce the risk of flares; and avoiding trigger foods (e.g. spicy foods, fried foods, alcohol, caffeine).
  • Bowel rest: If your symptoms are severe, you may need to rest your bowel for a few days to several weeks. During recovery, you may be restricted to a liquid diet with nutritional supplements until you are better able to digest soft food. Hospitalization and enteral nutrition (a feeding tube) may be needed in some cases.
  • Prescription drugs: A variety of prescription medications may be used to treat different aspects of Crohn's disease, from inflammation to infection and more. Options include aminosalicylates, such as Asacol (mesalamine); antibiotics, such as Cipro (ciprofloxacin); corticosteroids, such as prednisone; immune modulators, such as methotrexate; and biologics, such as Humira (adalimumab).
  • Over-the-counter (OTC) remedies, such as pain relievers and antidiarrheals

While surgery is not a cure, it is often needed to avoid severe complications, such as a bowel rupture.

Approximately 70% of people with Crohn's disease will require surgery within 10 years of their initial diagnosis.

Among the surgeries commonly performed in people with Crohn's disease:

  • Bowel resection is the removal of a diseased portion of the large intestine.
  • Colectomy is the removal of a diseased part of the colon.
  • Proctocolectomy is the removal of the colon and rectum.
  • Strictureplasty is used to widen a narrowed intestinal passage.

Some surgeries may require an ostomy, a temporary or permanent procedure in which the intestines are redirected to a hole in your abdomen.


Living with Crohn's disease can be physically and emotionally challenging.

Fortunately, there are things you can do to reduce the risk of flares and ensure that the disease doesn't interfere with the quality of your home or work life.

Among the key tips for coping with Crohn's disease:

  • Eat four to six small meals a day.
  • Keep well hydrated.
  • Drink slowly to avoid gulping air and causing gas and bloating.
  • A daily, 30-minute workout can help normalize your bowel function and boost your mood and energy levels.
  • Quitting cigarettes is essential to achieving sustained disease remission. Speak with your doctor or health insurer about available smoking cessation aids.
  • Avoid staying out in the sun too long or getting overheated, both of which can trigger diarrhea.
  • Mind-body therapies can help relieve stress which may, in turn, reduce the severity, frequency, or persistence of Crohn's disease flares.
  • Find a local support group through the national Crohn's and Colitis Foundation.

A Word From Verywell

With the introduction of newer, more effective medications, people with Crohn’s disease are able to live fuller, more productive lives than ever before.

Medication is, ultimately, only part of the solution. To ensure long-term disease control, you need to forge a consistent and fully interactive relationship with your gastroenterologist.

By educating yourself and working cooperatively with your medical team, you'll be better able to spot problems before they escalate and prevent many of the otherwise avoidable complications of the disease.

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Article Sources
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