Crohn's Disease: Symptoms, Causes, Treatment

Medically Reviewed by Poonam Sachdev on July 12, 2023
15 min read

Crohn's disease is a condition that causes swelling, or inflammation, in part of your digestive system. It can affect any part of your digestive tract, but  most often involves your small intestine and colon (large intestine).

Crohn's and another disease, ulcerative colitis (UC), are part of a group of conditions called inflammatory bowel disease (IBD).

There's no cure for Crohn's, but treatment can ease your symptoms and help you enjoy a full, active life.

People with Crohn's disease can have intense symptoms, followed by periods of no symptoms that may last for weeks or years. The symptoms depend on where the disease happens and how serious it is. 

What are the first signs of Crohn's disease?

Early signs of Crohn's disease can easily be mistaken for other conditions. Theyh may include:

  • Frequent diarrhea
  • Abdominal pain and tenderness
  • Unexplained weight loss
  • Blood in your poop

Other symptoms of Crohn's disease

When it advances, you might notice:

  • Nausea
  • Tiredness
  • Joint pain
  • Fever
  • Long-lasting diarrhea, often bloody and with mucus or pus
  • Weight loss
  • Mouth sores

Learn more about Crohn's disease symptoms.

There are five types of Crohn's, based on which part of your digestive tract is affected.

  • Ileocolitis, the most common form of Crohn's disease, involves your colon and the last part of your small intestine (called the ileum or terminal ileum).
  • Crohn's colitis or granulomatous colitis affects only your colon.
  • Gastroduodenal Crohn's disease affects your stomach and the first part of your small intestine (called the duodenum).
  • Ileitis affects your ileum.
  • Jejunoileitis causes small areas of inflammation in the upper half of your small intestine (called the jejunum).

Doctors aren't sure what causes Crohn's disease. Some people think of it as an autoimmune disease. Research suggests that long-term inflammation may not happen because your immune system attacks your own body but because it attacks a harmless virus, bacteria, or food in your gut.

Is Crohn's disease contagious?

Although its causes are unclear, it can't spread from person to person.

A few things can make you more likely to get Crohn’s:

  • Genes. Crohn's disease is often inherited. About 20% of people who have it have a close relative with either Crohn's or UC.
  • Age. Though it can affect people of all ages, it's mostly an illness of the young. Most people are diagnosed before age 30, but the disease can affect people in their 50s, 60s, 70s, or even later in life.
  • Smoking. This is one risk factor that's easy to control. Smoking can make Crohn's more serious and raisethe odds that you’ll need surgery.
  • Medications. Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen, and similar medications don't cause Crohn's disease, but they can lead to inflammation of the bowels that makes it worse.
  • Where you live. People who live in urban areas or industrialized countries are more likely to get Crohn's.
  • Diet. If you eat a lot of high-fat or processed foods, your odds could go up.
  • Infection. Bacteria linked to Crohn's disease include Mycobacterium aviumparatuberculosis, which causes a similar condition in cattle, along with a type of Escherichia coli.


Crohn's disease epidemiology

The disease is most often found in North America and Western Europe, where it affects 100-300 out of every 100,000 people.

In the U.S., more than half a million people have it. Researchers think cases are increasing in the U.S. and some other nations.

Crohn's disease seems to affect men and women at similar rates. People of northern European or central European Jewish (Ashkenazi) descent are at  highest risk.

If you have symptoms of Crohn's disease, your doctor will try to figure out whether you have Crohn's disease or another condition like ulcerative colitis.

Tests for Crohn's disease

Your doctor will review your medical history and talk about your symptoms. Then they might order some lab tests, such as:

  • Blood tests, including blood counts
  • Stool samples to rule out infections as the cause of diarrhea
  • Imaging tests:
    • MRI. This shows your doctor a clear picture of the inside of your body without using radiation.
    • CT scan. This test uses X-rays to make detailed images of your internal organs.
  • Endoscopy. Your doctor might send you to a gastroenterologist to get one of these:
    • Balloon-assisted enteroscopy. This test uses balloons that inflate and deflate to pull a flexible tube called an endoscope through your small intestine. A tiny camera on one end gives a view of the inside of your guts.
    • Capsule endoscopy. You'll swallow a tiny, pill-sized camera to give the doctor a closer look at your small intestine.
    • Upper endoscopy. The doctor performs this to see your esophagus, stomach, and duodenum.
    • Colonoscopy or sigmoidoscopy. This gives the doctor a clear picture of your intestines and lets them take a tissue sample to study.

Learn more about how doctors diagnose Crohn's disease.

Crohn's disease often gets worse over time. An endoscopy can show your doctor how much inflammation you have in your intestines. That, along with your symptoms, helps them know how advanced your Crohn's disease is.

Mild Crohn's disease

People with mild Crohn's disease have symptoms like diarrhea, but they don't have:

  • Fever
  • Major weight loss
  • Signs of infection or blockages in their intestines

Moderate to severe Crohn's disease

Along with diarrhea and abdominal pain or tenderness, you could have:

  • Fever
  • Nausea or vomiting
  • Noticeable weight loss

Severe Crohn's disease

This stage may bring:

  • Blockages or infections in your intestines 
  • Symptoms that don't respond to treatment
  • Symptoms in places other than your digestive tract, such as your skin, eyes, joints, liver, and kidneys

There's no single treatment that's right for everyone with Crohn's disease. Your treatment will depend on what's causing your symptoms and how serious they are. Your doctor will try to reduce the inflammation in your digestive tract and keep you from having complications.

Medications for Crohn's disease

Crohn's disease is mostly treated with medications, including:

  • Anti-inflammatory drugs. Examples include mesalamine (Asacol, Lialda, Pentasa), olsalazine (Dipentum), and sulfasalazine (Azulfidine). Side effects include upset stomach, headache, nausea, diarrhea, and rash. These medicines are used only in mild cases.
  • Corticosteroids, a more powerful type of anti-inflammatory drug. Examples include budesonide (Entocort) and prednisone or methylprednisolone (Solu-Medrol). If you take these for a long time, side effects can be serious and may include bone thinning, muscle loss, skin problems, and a higher risk of infection.
  • Immune system modifiers (immunomodulators), such as azathioprine (Imuran, Azasan) and methotrexate (Rheumatrex, Trexall). It can take up to 6 months for these drugs to work. They also bring a higher risk of infections that could be life-threatening.
  • Antibiotics such as ciprofloxacin (Cipro) and metronidazole (Flagyl) to fight infections in your digestive system caused by Crohn's disease. Metronidazole can cause a metallic taste in your mouth, nausea, and tingling, or numbness of your hands and feet. Ciprofloxacin can cause nausea and tears in your Achilles tendon.
  • Drugs for diarrhea including loperamide in small doses.

Biologic medicines may be included in your treatment if you have moderate to severe Crohn's disease. The anti-tumor necrosis factor drugs are often the first choice and include:

  • Adalimumab (Humira)
  • Adalimumab-atto (Amjevita)
  • Certolizumab pegol (Cimzia)
  • Infliximab (Remicade)
  • Infliximab-abda (Renflexis)
  • Infliximab-dyyb (Inflectra)
  • Infliximab-axxq (Avsola)

Other biologics approved for Crohn's disease include:

  • Natalizumab (Tysabri)
  • Risankizumab-rzaa (Skyrizi)
  • Ustekinumab (Stelara)
  • Vedolizumab (Entyvio)

Once you start treatment, your doctor will check back in several weeks to see how well it works. You'll continue treatment until you reach remission (when your symptoms ease). When that happens, your doctor may prescribe "maintenance therapy" to keep your symptoms at bay. If you don't get better, you'll need stronger treatment. Your doctor may suggest nutritional supplements, too.

Learn more about Crohn's disease medications.

Surgeries for Crohn's disease

About 66%-75% of people with Crohn's disease will need surgery. It can help with complications or when medications don't work. Common procedures include:

  • Resection. Your surgeon removes the diseased part of the bowel and joins the two healthy ends together. Many people are symptom-free for years afterward, but it isn't a cure. Crohn's disease often comes back at the site of the connection, called the anastomosis.
  • Ileostomy. You might need this if your rectum is diseased and the doctor can't use it for an anastomosis. This procedure connects your intestine to the skin of your torso. It leaves an opening in your skin, where body wastes collect in a pouch that you can empty.

Complementary and alternative treatment options for Crohn's disease

When you use nonmedical treatment options instead of medical ones, they're called alternative therapies. Those used along with medical treatments are called complementary therapies.

Medication is the main treatment for Crohn's disease, but many people use complementary therapies to help ease symptoms. They include:

  • Mind-body therapies such as relaxation, meditation, hypnosis, acupuncture, yoga, and exercise
  • Dietary supplements like omega-3 fatty acids and curcumin
  • Probiotics, foods, or supplements containing microorganisms that boost "good" bacteria in your gut
  • Medical cannabis

Research on many of these treatments is ongoing. Talk with your doctor before trying any of them.

Home remedies for Crohn's disease

Some things you can do on your own may also help relieve your Crohn's symptoms.

  • Avoid NSAIDs. Use acetaminophen instead.
  • Quit smoking. This may help reduce flare-ups, lessen the amount of medication you need, and lower your chances of surgery.
  • Manage stress. Stress doesn't cause Crohn's disease, but it can make symptoms worse. Try some of the mind-body therapies above, such as meditation or yoga.

Find out about the latest treatments for Crohn's disease.

White people are most likely to develop Crohn's disease. But cases of Crohn's disease and other types of IBD have been increasing among Black, Hispanic, and Asian people, as well as those of other ethnicities.

Doctors may be less likely to look for IBD in minorities, which could lead to later diagnosis and treatment. This may be one reason Black people tend to have more serious cases of IBD than white people, and the condition is more likely to seriously affect their daily lives.

Studies report that Black people with IBD are also less likely to get advanced treatments such as biologics and immunomodulators. They're less likely to be in remission from Crohn's disease, more likely to have surgery for it, and more likely to get complications after the surgery.

All the reasons for these differences aren't clear. Things that may play a role include:

  • Access to medical care
  • Insurance coverage
  • Bias among doctors
  • Differences in diet and environment

Crohn's disease causes two types of complications:

  • Local, which affect just your intestines
  • Systemic, which affect your whole body. You might also hear them called extraintestinal complications.

Local complications of Crohn's disease include:

  • Abscess. This pocket of pus occurs because of a bacterial infection. It can form on the walls of your intestines and bulge out, or you might get one near your anus that looks like a boil. You'd notice swelling, tenderness, pain, and fever.
  • Bile salt diarrhea. Crohn's disease most often affects the lower end of your intestine (ileum). This part usually absorbs bile acids, which your body makes to help it absorb fat. If your body can't process the fat, you could get this type of diarrhea.
  • Fissure. This is a painful tear in the lining of the anus. It can cause bleeding during bowel movements.
  • Fistulas. Sores or ulcers can turn into openings called fistulas that connect two parts of your intestine. They can also tunnel into nearby tissues, such as the bladder, vagina, and skin.
  • Malabsorption and malnutrition. Crohn's disease affects your small intestine—the part of your body that absorbs nutrients from food. After you've had it for a long time, your body may no longer be able to get enough nutrients from what you eat.
  • Small intestinal bacterial overgrowth. Your gut is full of bacteria that help you break down food. When this happens higher up in your digestive tract than usual, you can get gas, bloating, abdominal pain, and diarrhea.
  • Strictures. These narrowed, thickened areas of your intestines result from the inflammation that comes with Crohn's disease. They can be mild or serious depending on how much of your intestine is blocked. Symptoms include cramping, abdominal pain, and bloating.

Systemic complications include:

Arthritis. Joint inflammation, which leads to pain, swelling, and lack of flexibility, is the most common systemic complication. Three types of arthritis sometimes come with Crohn's disease:

  • Peripheral. This type affects large joints in your arms and legs, such as your elbows, knees, wrists, and ankles.
  • Axial. This type affects your spine or lower back (the doctor may call it your sacroiliac joint).
  • Ankylosing spondylitis. This more serious type of spinal arthritis is rare among people with Crohn's, but it can happen. It can also lead to inflammation in your eyes, lungs, and heart valves.

Skin problems. These are the second most common systemic complications. Those most often linked to Crohn's include:

  • Erythema nodosum. These small, tender, red nodules usually show up on your shins, ankles, and sometimes arms.
  • Pyoderma gangrenosum. These pus-filled sores often follow an injury or other skin trauma. They often appear on your legs but can show up anywhere.
  • Skin tags. These small flaps of skin are common in people with Crohn's disease, especially around the anus.
  • Mouth ulcers. You might hear them called canker sores. They form between your gum and lower lip or along the sides and bottom of your tongue.

Bone loss. Medications like steroids can lead to bone loss, a condition known as osteoporosis. They can:

  • Stop your body from absorbing calcium, which it needs to build bones
  • Make your body get rid of calcium when you pee
  • Boost production of cells that break down bones
  • Lower the number of cells that help form bones
  • Lower your body's output of estrogen, which also helps build bones

The proteins that cause inflammation can also change the speed at which your body removes and makes bones.

Lack of vitamin D. If your body can't absorb vitamin D because of Crohn's damage to your small intestine, or if part of your small intestine has been removed, you're less likely to be able to absorb calcium and make new bones.

Eye problems. Inflammation due to Crohn's disease can affect your eyes in several ways. Common conditions include:

  • Episcleritis. Inflammation of the area just below the conjunctiva (the clear tissue that covers the inside of your eyelids and the white of your eye) is the most common complication of Crohn's. It can affect one eye or both the eyes. You'll notice pain, itching, burning, and severe redness, but it won't usually affect your vision.
  • Scleritis. This condition causes constant pain that gets worse when you move your eyes.
  • Uveitis. This is a painful inflammation of the uvea, the middle layer of your eye. It can cause blurry vision, light sensitivity, and redness.

Kidney problems. These organs can be affected  because they play a role in processing waste and are near your intestines. Potential issues include:

  • Kidney stones. They're a common problem with Crohn's. One type happens when a salt called oxalate gets absorbed into your kidneys and turns into stones. Another type, called uric acid stones, form when your body can't absorb all the uric acid that it makes.
  • Hydronephrosis. This happens when the ileum (where the small intestine meets the large) swells because of Crohn's and puts pressure on the ureter,  the tube that carries urine from your kidney to your bladder. When urine can't drain as it should, your kidney swells, and scar tissue can form.
  • Fistulas. In addition to forming within your intestines, fistulas can form between the intestine and other organs, like your bladder or ureter.

Liver problems. Your liver processes everything you eat and drink. It can get inflamed as a result of Crohn's disease treatment or the disease itself. You're likely to only notice low energy and fatigue unless you get a more serious problem. Among the most common issues are:

  • Fatty liver disease. When your body doesn't process fats well, they can build up in your liver. Steroids can also cause fatty liver disease.
  • Gallstones. When Crohn's disease affects the ileum, it can't process bile salts, which help dissolve cholesterol. The cholesterol can form stones that block the opening between your liver and the bile duct.
  • Hepatitis. Long-term liver inflammation can result from Crohn's disease itself.
  • Pancreatitis. Inflammation of your pancreas can result from both gallstones and medications. It can cause pain, nausea, vomiting, and fever.

Physical development problems. Crohn's can start at any age. When kids get it, parents are likely to notice:

  • Growth failure. Kids  who haveh Crohn's  are likely to be shorter and weigh less than those who don't. They may stop getting taller before their symptoms start.
  • Delayed puberty. Kids with Crohn's disease are likely to start puberty later.

Most studies link Crohn's disease to a very small but real increase in the risk of early death. Usually, the causes are not Crohn's disease itself but related complications, which include infections, a tear in the bowels, and deadly reactions to steroids and other treatments.

Daily life with Crohn's disease has its challenges. Your symptoms can leave you feeling tired and drained. They may also be embarrassing. You might avoid socializing or other activities you enjoy.

The most important step in managing Crohn's disease is to work closely with your doctor to find the right treatment. But self-care is also essential.

Crohn's disease diet

Foods don't seem to cause Crohn's disease, but soft, bland things may cause fewer symptoms than spicy or high-fiber foods when the disease is active. Most doctors try to be flexible in planning the diets of people with Crohn's.

You might also try an elimination diet, which can help you figure out which foods trigger symptoms of Crohn's disease. You'll remove things from your diet one at a time to see what happens. Work with your doctor or a dietitian to make sure you don't miss out on any nutrients while you're doing it.

See how you feel after cutting back on:

  • Greasy or fried foods
  • Processed foods
  • Dairy products
  • Carbonated drinks
  • Caffeine
  • High-fiber foods like nuts, seeds, and raw vegetables
  • Foods that can cause gas, such as beans and cruciferous veggies

Cost of Crohn's disease

Crohn's disease can take a toll on your pocketbook as well as your body. One study reported that people with IBD spent more than $2,200 out-of- pocket for health care each year,. That's more than twice what people without IBD paid.

Medications for Crohn's disease can be very expensive. For example, a single dose of a biologic drug can cost thousands of dollars before insurance.

Work time lost to sick days and medical appointments can add up, too. Research shows that people with IBD lose about $3,000 in wages per year.

Managing Crohn's disease

To minimize flare-ups and protect your health, take these steps:

Get enough sleep. Losing sleep can make inflammation worse and affect your mood. But many people with Crohn's disease have trouble getting enough shut-eye, especially when they're having a flare. Adopt healthy sleep habits: Go to sleep and get up at about the same time every day, and avoid electronic devices around bedtime.

Stay active. Regular exercise helps with symptoms of Crohn's disease, boosts mood, and reduces stress. Low-impact, moderate activities like walking, biking, swimming, and yoga are often best for people with IBD. Talk with your doctor about what workouts might be right for you.

Stay hydrated. It's easy to get dehydrated when your body is losing lots of fluid through diarrhea. Make sure you drink enough fluids, especially when you're exercising or it's hot outside. Water is best, since juices and sodas might make your symptoms worse. A good rule of thumb is to drink eight glasses of water a day, though some people need more than that and some less.

Track your symptoms. Whether you use a smartphone app or a paper notebook, keeping track of your symptoms can help you recognize flare-ups early on and figure out what might trigger them. It can also help your doctor understand what your condition looks like between visits. Let your doctor know if you have signs of a flare.

Crohn's disease and mental health 

Dealing with a lifelong disease like Crohn's disease can wreak havoc on your quality of life and your emotions. That's one reason people with Crohn's disease are at a higher risk of depression than others. Stress and anxiety can affect you, too, and can make your symptoms worse.

If you're feeling sad, stressed, or overwhelmed:

Try a support group. Talking to people who are in the same boat can be reassuring and uplifting. Support groups are also good places to hear about the latest therapies and lifestyle changes that have helpedothers. There are plenty of online support groups. If you prefer an in-person group, your doctor may be able to help you find one.

Seek therapy. Look for a mental health professional experienced in treating people with IBD. Cognitive behavioral therapy, gut-directed hypnotherapy, or mindfulness therapy are some of the types of psychotherapy you might consider.

Talk with your doctor. They may recommend antidepressants or anti-anxiety medications. These medications may be most effective when you use them together with psychotherapy.

Crohn's disease doesn't usually shorten your life. Most people with Crohn's disease are able to live productive and fulfilling lives, especially when they get effective treatment.

Is there a cure for Crohn's disease?

Existing treatments can't cure Crohn's disease, but they can help relieve symptoms, reduce flare-ups, and help you avoid possibly serious complications.

What to expect with Crohn's disease

Crohn's disease is a lifelong disease whose course varies a lot from person to person. Doctors can't predict how it will affect you.

It might be mild or serious. You could have periods of symptoms that can last days, weeks, or months, followed by periods of remission that can last days, weeks, or years. There's often no way to predict when you'll have a flare.

Ulcerative coitis, the other form of IBD, has symptoms very similar to those of Crohn's disease. It also tends to affect people younger than age 30.

UC causes inflammation only in the colon, while Crohn's disease can affect any part of your digestive tract from the mouth to the anus. Crohn's disease usually affects your bowel in patches, but with UC, you have continuous stretches of inflammation.

Other conditions that could look like Crohn's disease include:

  • Irritable bowel syndrome , a common digestive disorder whose symptoms may include abdominal pain, diarrhea, constipation, gas, or bloating.
  • Celiac disease, an immune system reaction to gluten (a protein found in wheat, barley, and rye) that can damage your intestines. Symptoms include diarrhea, tiredness, and weight loss.
  • Food allergy, in which certain foods trigger an allergic reaction in your body. Symptoms can include abdominal pain, diarrhea, and nausea. Some people have much more serious symptoms such as trouble breathing.
  • Colon cancer, which could cause weight loss, abdominal pain, and blood in your poop.

While there's no cure for Crohn's disease, treatment can ease symptoms and help prevent complications. Work with your doctor to find the right treatment. Good self-care can also help minimize flares and protect your health