Overview Illustration - Crohn's Disease

What Is Crohn's Disease?

Crohn's disease causes inflammation in the gastrointestinal tract. Belly pain, diarrhea, fatigue, and weight loss are common.

Crohn's disease is a type of inflammatory bowel disease (IBD). IBD causes inflammation in the gastrointestinal (GI) tract. 

Crohn's disease can affect any area in the GI tract, from the mouth to the anus. But inflammation usually occurs in the ileum. The ileum is the end of the small intestine. Belly pain, diarrhea, fatigue, and weight loss are common symptoms of Crohn's disease.

There is no cure for Crohn's disease. But treatment and lifestyle changes can manage symptoms. It's possible to be symptom-free for several years. If untreated, Crohn's disease can cause life-threatening complications. It may also cause serious health issues, like:

  • Anemia (low red blood cell count)
  • Arthritis
  • Glaucoma
  • Liver disease 
  • Gallbladder disease

More than 500,000 people in the United States live with Crohn's disease. You can develop the condition at any age. But it most commonly appears in people in their 20s.

Types of Crohn's Disease

Crohn's disease can affect various parts of your GI tract. There are five types of Crohn's disease, including:

  • Ileocolitis: This is the most common type. It affects the end of your small intestine and colon. Your colon is the longest part of your large intestine.
  • Ileitis: This only affects the end of your small intestine.
  • Gastroduodenal Crohn's: This causes inflammation in your stomach. It also affects your duodenum. The duodenum is the first part of your small intestine.
  • Jejunoileitis: This causes inflammation in your jejunum. The jejunum is part of the upper half of your small intestine.
  • Crohn's (granulomatous) colitis: This causes inflammation in your colon.

Crohn's Disease Symptoms

Symptoms depend on the type of Crohn's disease and vary between people. They may range from mild to severe. People with Crohn's disease may have periods of remission when they don't have any symptoms. Flares happen when symptoms worsen.

Some of the most common symptoms of Crohn's disease include:

  • Diarrhea
  • Cramps
  • Abdominal pain
  • Weight loss
  • Anemia
  • Eye redness
  • Eye pain
  • Fatigue
  • Fever
  • Joint pain
  • Nausea
  • Appetite loss
  • Red bumps that form under the skin
  • Bloody stools
  • Pain or drainage around your anus
  • Kidney stones

If untreated, Crohn's disease may cause complications like:

  • Malnutrition: Gut inflammation makes it hard to absorb nutrients.
  • Bowel obstruction: Scars can narrow your large intestine. That may cause a blockage.
  • Ulcers: Open sores can develop anywhere from your mouth to your anus.
  • Fistulas: Inflammation may spread through your intestine wall. That can create a tunnel between two organs. Or it may make an opening from an organ to the outside of your body.
  • Abscess: These are painful, pus-filled pockets.
  • Anal fissures: These are painful tiny tears in your anal tissue. You may notice blood in your stool with anal fissures.

What Causes Crohn's Disease?

Once, researchers thought poor diet and stress were the culprits of Crohn's disease. However, while diet and stress can worsen symptoms, what causes Crohn's disease is unclear. 

Risk Factors

Some factors that affect your risk include:

  • Genes: Some evidence suggests IBD runs in families. If you have family members with Crohn's disease, your risk increases. As many as 20% of people with Crohn's disease have a close family member with the condition.
  • Immune system: Your immune system may attack healthy cells in your digestive tract.
  • Smoking: Smoking may double your risk. Some evidence suggests that smoking also worsens symptoms.
  • Medications: Birth control pills, ibuprofen, aspirin, and antibiotics may increase your risk.

How Is Crohn's Disease Diagnosed?

No single test detects Crohn's disease. Instead, your healthcare provider may use many tests. They may ask you about your and your family's medical history. 

Your healthcare provider may also physically examine you. For example, they may keep an eye out for bloating. Using a stethoscope, they can listen for abnormalities in your abdomen. They may also tap on your stomach to check for pain. 

Other tests can rule out other conditions and measure the severity of your condition. They may include:

  • Blood tests: Too many white blood cells may indicate an infection or inflammation. Also, too few red blood cells may detect anemia. One in three people with Crohn's disease has anemia.
  • Fecal sample: This tests for parasites that cause GI issues.
  • Upper GI series: This uses x-rays to check how well your digestive tract functions.
  • ColonoscopyThis is an outpatient procedure. During a colonoscopy, your healthcare provider uses an instrument to view the inside of your colon. They may also collect and test tissue samples.
  • Computed tomography (CT) scan: This is an imaging test. It allows your healthcare provider to detect inflammation. They can also see what parts of your digestive tract are inflamed.
  • Upper GI endoscopy: This is an invasive procedure. Your healthcare provider will thread a very thin tube with a camera into your throat. The tube has a camera on the end that helps them check for issues.

Treatments for Crohn's Disease

There's no cure for Crohn's disease. But many treatments can help. A mix of treatments can reduce inflammation. They can also lower your risk of complications.

Your healthcare provider may suggest medications, such as:

  • Corticosteroids: These are steroids that fight inflammation in your GI tract. They also keep your immune system from attacking healthy cells.
  • Aminosalicylates: These medications also fight inflammation.
  • Immunomodulators: These suppress your immune system. That prevents it from targeting healthy cells.
  • Biologic therapies: These medications reduce inflammation in your GI tract.
  • Antibiotics: You may need these to prevent infections if you have abscesses or fistulas. 
  • Pain relievers: Non-steroidal anti-inflammatory drugs (NSAIDs) are rough on your GI tract. Common NSAIDs include ibuprofen and aspirin. Tylenol (acetaminophen) is a good alternative. Talk to your healthcare provider if you need over-the-counter (OTC) pain medicine.
  • Anti-diarrheal medication: These medications stop diarrhea.

Other methods that treat Crohn's disease include:

  • Bowel rest: Your healthcare provider may advise you not to consume anything. Instead, you will receive nutrients through a feeding tube or intravenously (IV). Or you might only drink some liquids. If your symptoms are intense, bowel rest eases the pain in your intestines. It may last several days or weeks.
  • Nutritional therapy: A special diet can combat malnutrition. Your healthcare provider may suggest a low-fat, vegan, or gluten-free diet.
  • Surgery: This can stop bleeding and remove blockages in your intestine. Some also fix tears and remove damage to your GI tract. About 60% of people with Crohn's disease will need surgery.

How To Prevent Crohn's Disease Flares

There's no way to prevent Crohn's disease. But you can take steps to reduce your risk of flares. Some lifestyle changes that may help include:

  • Pay special attention to your diet: You may find that soft, bland foods are easy to digest. Spicy or high-fiber foods can be rough on your GI tract. Also, limit dairy, greasy foods, or foods that cause gas. A food journal can keep track of what foods worsen your symptoms.
  • Try complementary and alternative therapies: These include acupuncture, massage, or Tai Chi. They may help alleviate pain. Reducing pain can improve your overall quality of life. Some may even boost immunity. 
  • Manage your stress: Meditation, yoga, or deep breathing can help prevent a flare. They may also help your disease feel less overwhelming.
  • Quit smoking: Quitting smoking may prevent flares. You'll also reduce your risk of surgery.
  • Limit caffeine and alcohol: Both may worsen symptoms. It's best to track if you have flares after consuming caffeine or alcohol.

Symptoms of Crohn's disease can be painful. They may interfere with your daily activities. It's normal to feel frustrated. It may help to build a support system to help your disease feel less overwhelming. Talking to mental health provider may help, too.

Comorbid Conditions

Research has found that, in general, people with IBD have increased risks of several health conditions compared to the general population. Specifically, the inflammation caused by Crohn’s disease may bring about other complications.

Colorectal Cancer

Some evidence suggests that IBD increases the risk of colorectal cancer. But in the United States, that risk has steadily decreased due to cancer screenings and treatment advancements. 

Risk factors for colorectal cancer include duration and severity of IBD, family history of cancer, and how much inflammation you have.

Heart Disease

The inflammation caused by Crohn’s disease may also cause atherogenesis. Atherogenesis happens when plaque builds up in your arteries, leading to coronary artery heart disease. 

Also, Crohn’s and heart disease share risk factors, such as being overweight and obese.

Joint Pain 

Joint pain is one of the most common conditions comorbid with Crohn’s disease, occurring in nearly one-third of people with IBD. In some cases of Crohn’s disease, people may notice pain in their wrists, knees, or ankles. 

Although the cause of joint pain in Crohn’s disease is unknown, some evidence suggests that inflammation in the GI tract increases the risk.

Kidney Disease

Renal disease occurs in as many as 23% of people with IBD. One of the most common complications is end-stage renal disease (ESRD), the final stage of chronic kidney disease (CKD). 

Like other comorbid conditions, ESRD possibly occurs due to inflammation in the GI tract.

Liver Disease

Liver disease occurs in 3% to 50% of people with IBD. Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases co-occurring with IBD. 

Family history, inflammation, and environmental triggers may increase the risk of liver disease.


Per one study published in 2017 in the European Journal of Pain, researchers found that 75% of participants with IBD reported migraines or severe headaches within the previous three months. The researchers concluded that migraine is nearly two-fold higher among people with IBD than the general population.

Your GI tract constantly communicates with your brain. Therefore, your gut health can strongly affect your brain. That communication is also known as the gut-brain axis, possibly explaining the presence of migraine among people with IBD.

Respiratory Disease

Although rare, some people with IBD report respiratory diseases. Research has found that the lungs and GI tract originate from the same origins during embryological development. That similarity may explain the relationship between the two organs.

Living With Crohn's Disease

Crohn's disease can be unpredictable. Some people rarely have symptoms, and others have consistent and frequent flares. Also, Crohn's disease is rarely fatal. In fact, most people with the condition live healthy lives. But in any case, Crohn's disease can pose obstacles to participating in your daily activities. 

Because Crohn's disease is a chronic condition, managing your symptoms and prioritizing your health are key to living comfortably. Taking your medications as prescribed by your healthcare provider can help manage your symptoms. But for some people, additional ways to help alleviate symptoms may include:

  • Focusing on your diet: There is no special diet for Crohn's disease. Instead, concentrating on what foods do and do not work for you would be best. For instance, you may reduce your caffeine intake if you have diarrhea. It may help to keep a food journal. Keeping track of what foods upset your stomach will help you determine what to avoid. 
  • Trying complementary and alternative medicines (CAM): CAM therapies include meditation, acupuncture, or hypnosis, which may help you relax. CAM therapies may also help alleviate pain or improve immunity.
  • Taking care of your mental health: Crohn's disease can negatively impact your mental health. If you're experiencing feelings of stress or helplessness, it may help to build a support system of family and friends. Also, talking to a mental health counselor can make your condition feel less overwhelming. In particular, you may find comfort in discussing your symptoms with people specializing in IBD or chronic illnesses.

A Quick Review

Crohn's disease is a type of IBD that causes inflammation in the GI tract. Symptoms usually come and go. They may include belly pain, diarrhea, fatigue, and weight loss.

There is no cure for IBD. But your healthcare provider may prescribe different medications to help with symptoms. They may also advise bowel rest, special diets, or surgeries.

You can take steps to prevent flares. Avoiding foods that irritate your GI tract, reducing stress, and quitting smoking may help with the pain. 

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Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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