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A male with stomach pain representing symptoms of Crohn’s or colitis and an illustration of a hot water bottle in the corner.

December 1, 2022 • read

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What’s the difference between Crohn’s and colitis?

Crohn’s and colitis are often rolled together, so it’s understandable if you think they’re the same thing. And once you’re in the realm of diarrhea, bloody stool, and indigestion, does it even matter what the name of a condition is? You might be surprised, but when it comes to effective treatment, the differences between the two illnesses matter. Here’s the scoop on Crohn’s vs. colitis.

What’s Colitis?

Colitis isn’t an actual diagnosis. Instead, it’s a general term for colon inflammation or irritation. This means that colitis can be temporary if a virus causes it, or it can refer to a chronic condition caused by inflammatory bowel disease (IBD).

There are different causes of colitis, each requiring different treatments. The variety of colitis you’re diagnosed with depends on what’s causing it and what your symptoms are.

What’s Crohn’s disease?

Crohn’s disease is a chronic bowel disease that causes inflammation in your digestive tract, which makes it a form of colitis.

Normal digestive tracts are full of bacteria, most of which are harmless or beneficial to your body. When you have Crohn’s, however, your immune system mistakenly views this bacteria as a threat and mounts an attack on it. This results in chronic inflammation, setting off all the unpleasant symptoms of the disease.

The disease can result in serious infections, and in rare cases, you can die from Crohn’s disease as a result of these. However, managing your condition properly and reporting any unusual symptoms to your doctor will mitigate this risk.

Due to its complications, individuals with Crohn’s disease have a life expectancy of five to eight years less than those without it. Individual longevity depends on a number of factors, however, including diet, lifestyle, and genetics.

What are the symptoms of Crohn’s disease?

Because it affects the digestive tract, the majority of Crohn’s disease symptoms tend to be gastrointestinal. These include:

  • Pain in the lower right side of the abdomen
  • Chronic diarrhea — with or without blood
  • Bloating after eating
  • Fecal urgency
  • Constipation
  • Rectal bleeding
  • Feelings of partially completed bowel movements

The condition isn’t restricted to just the digestive tract, however. Due to its wide-reaching effects, it may also cause:

  • Vision changes, redness, and pain in the eyes
  • Canker sores
  • Skin issues
  • Fatigue
  • Weight loss
  • Fever
  • Joint pain
  • Menstrual dysfunction

What are the symptoms of colitis?

There are a number of different types of colitis. While many share similar symptoms, they have different underlying causes and require distinct treatments.

Allergic colitis

Allergic colitis or eosinophilic colitis presents most often within the first six months of life, but can occur at any age. Symptoms may include:

  • Diarrhea, sometimes bloody
  • Abdominal pain
  • Issues around eating including refusal to eat, loss of appetite, or not eating enough
  • Poor growth, difficulty gaining weight, or weight loss
  • Nausea
  • Vomiting
Ulcerative colitis

According to Crohn’s and Colitis Canada, ulcerative colitis (UC) and Crohn’s disease are both types of IBD. With UC, the symptom you’re most likely to experience is diarrhea, which may be bloody or contain mucous. You may also experience:

  • Abdominal pain or cramping
  • Fecal urgency
  • Frequent small bowel movements
  • Anemia
  • Weight loss
  • Tiredness and low energy
  • Failure to thrive (in children)
Microscopic colitis

There are a few different types of microscopic colitis, but they all manifest with similar symptoms. These often include:

  • Chronic, watery diarrhea
  • Weight loss
  • Abdominal pain
  • Fecal urgency
  • Inability to control bowel movements
Ischemic colitis

The result of heart failure, atherosclerosis, and other cardiovascular conditions that reduce blood flow to the large intestine, ischemic colitis can develop slowly over time, or arrive suddenly. Due to its correlation with heart disease and other chronic conditions, it typically presents in those over 60 as:

  • Abdominal pain
  • Bloody stool
Pseudomembranous colitis

This condition is most often the outcome of a bacterial infection with Clostridium difficile (C. difficile) triggered by taking antibiotics. But, it can also be caused by other infections, drugs and medications, and inflammatory conditions. Symptoms may include mucousy diarrhea, though you’re most likely to experience:

  • Watery, sometimes bloody diarrhea
  • Stomach pain
  • Fever
  • Nausea

What causes colitis?

It’s not always possible to determine the exact cause of colitis. Ulcerative colitis is likely hereditary to a certain degree, as it tends to run in families. But doctors don’t know exactly why one person develops UC, and another doesn’t.

Sometimes, however, the origins of your colitis are clear. In many cases, the condition is brought on by bacterial, viral, or parasite infections. Heart disease and other conditions that constrict blood supply to the intestines may also be the source, while in other cases, autoimmune disease, previous radiation treatment of the bowels, or food allergy may be at its foundation.

With the exception of food allergies (usually seen in young babies), food isn’t the underlying cause of colitis. Diet can, however, play a role in colitis flare-ups. Many people find spicy and fried foods, alcohol, and caffeine make their symptoms flare up, while dairy triggers others.

What causes Crohn’s disease?

Doctors don’t know what exactly causes Crohn’s disease, but it likely includes an interplay between genetic, hereditary, and environmental factors.

If you have a parent or close relative with the disease, you’re also more likely to have it. And, living in an urban instead of a rural environment, and residing in a developed country make a diagnosis more likely too. Additionally, smokers are almost twice as likely to develop it.

So, how is Crohn’s disease diagnosed if doctors don’t even know what causes it? The diagnosis requires input from radiologic, endoscopic, or histological findings along with a compatible clinical history and examination.

In non-medical terms, that means taking images of the digestive tract or examining a piece of its tissue. This may be done by looking at your esophagus, stomach, and upper GI tract via an ultrasound, X-ray, or endoscope. Alternatively, your healthcare provider might recommend you check for Crohn’s disease via a colonoscopy.

Testing for Crohn’s disease can also involve blood testing and taking a stool sample. These function as complementary testing and can help determine disease severity or complications. They don’t make a conclusive diagnosis on their own, however.

How are ulcerative colitis and Crohn’s disease similar?

UC and Crohn’s overlap in several ways. For starters, they’re both forms of IBD. This means that they’re both chronic diseases that give rise to inflammation in the gastrointestinal tract.

Additionally, both conditions tend to result in many of the same symptoms. These often present as abdominal cramps, diarrhea, loss of appetite, and weight loss. And, while neither condition causes colon cancer, having either can increase your risk.

Differences between ulcerative colitis and Crohn’s disease

There are a few important differences between the conditions that help distinguish them. Because UC causes continuous ulcers throughout only the large intestine, bloody stool is more likely with this condition.

Crohn’s, on the other hand, can affect any part of the digestive tract with what are sometimes called skip lesions. This means it has a higher tendency for perianal, or rectal, inflammation. Features range from rectal itching to bleeding and, in severe cases, anal fissures or fistulas between organs. Additionally, since Crohn’s affects more of the digestive tract, it can cause oral lesions.

Can you have Crohn’s disease and colitis together?

Unfortunately yes, but it’s pretty rare. While Crohn’s can affect any part of the digestive tract, UC is limited to the large intestine. This makes it possible for both diseases to exist in the same person.

But, while both conditions fall under the heading of IBD, they seem to have distinct processes underlying them. Usually, this means that an individual with one diagnosis won’t end up with the other.

Treatments for Crohn’s

While there’s no cure for Crohn’s disease, it’s treatable. Colitis, however, is both treatable and curable in many cases. This is especially true when its underlying cause is a viral, bacterial, or parasitic infection.

Crohn’s disease treatment typically centres around immunosuppressant medications and steroids, like prednisone. Both aim to reduce the inflammation in the digestive tract to counter the uncomfortable symptoms of the disease.

If you have a more severe case, however, your healthcare provider might prescribe a class of drugs called biologics for your Crohn’s disease. These medications are made from proteins and other naturally-occurring substances that target specific parts of the immune system. Because they can’t go through the digestive system intact, these have to be injected or given through a drip.

The surgical removal of inflamed parts of the intestines is another treatment for both conditions. While this doesn’t cure Crohn’s, if you remove the entire colon, you can cure colitis. After all, you can’t have ulcerative colitis if you no longer have a colon. Surgery does come with risk, however, and isn’t necessary if you’re able to manage your condition with medication.

Many find that modifying their diet for their Crohn’s disease also helps. High-fibre and spicy foods, alcohol, and caffeine can trigger flare-ups with Crohn’s. Some find relief with a low-FODMAP diet, although it’s probably a good idea to see a dietitian if you’re planning to majorly overhaul the way you eat.

Colitis treatments are often similar to those of Crohn’s, as medications for colitis also centre around reducing inflammation.

In cases where bacteria or parasites are causing the condition, however, antibiotics are the first line of defence. In these specific cases, antibiotics remove the underlying root of the colitis, which usually leads to remission. Antibiotics are also helpful for certain complications from Crohn’s disease, like abscesses or fistulas.

And, as with Crohn’s, implementing a low-FODMAP diet for your colitis may be helpful in managing the condition. Since elimination diets can increase your risk of malnutrition, however, working with a dietitian or healthcare provider is best if you’re planning to follow this diet.

How online doctors can help with your Crohn’s or colitis

Digestive issues can affect every aspect of your life. Constant trips to the bathroom and chronic discomfort can make work impossible and life unenjoyable.

If you’ve been diagnosed with Crohn’s or colitis and are looking for additional medical support, Maple can help. With Maple, you can speak to a Canadian-licensed doctor via your phone, tablet, or computer in minutes, 24/7.

Seeing an online doctor can help you come to a more in-depth understanding of your condition and they can support you by developing a treatment plan. The doctor can also order additional testing or provide a specialist referral if necessary, and prescribe any medication you require.

If your digestive issues are keeping you from living your life, it’s time for more help. Speak to a doctor online today and take the first step towards controlling your Crohn’s or colitis.

This blog was developed by our team and reviewed by a medical professional.

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