• Types
  • Causes and risk factors
  • Symptoms
  • Complications
  • Diagnosis
  • Treatment
  • Prevention

The term “inflammatory bowel disease” (IBD) refers to a group of intestinal disorders characterised by prolonged inflammation of the digestive tract.

The digestive tract includes:

  • mouth
  • oesophagus
  • stomach
  • small intestine
  • large intestine

In this process, food is broken down, nutrients are extracted, and waste products are removed.

This normal process is disrupted by inflammation anywhere along the digestive tract. IBD can be extremely painful and disruptive. It may even be deadly in severe cases.

This article covers all the details about inflammatory bowel disease, including what causes it, and how it is treated.

Main types of IBD:

Approximately 1.6 million Americans are thought to suffer from inflammatory bowel disease (IBD), according to the Crohn’s & Colitis Foundation of America (CCFA).

Under the umbrella term of IBD are many diseases. Ulcerative colitis (UC) and Crohn’s disease are the two most common types.

UC involves inflammation of the large intestine.

Any part of the digestive tract can be affected by Crohn’s disease. It affects mostly the tail end of the small intestine, though.

IBD: What causes it?

IBD is not known to have a specific cause.

UC and Crohn’s disease are, however, primarily influenced by the following:

Genetics and family history

A person’s chances of developing IBD are much higher if they have a parent, sibling, or child who has it. This suggests that IBD may have a genetic component.

The immune system

It is possible that the immune system plays a role in IBD as well.

Pathogens, which cause diseases and infections, are normally trapped and destroyed by the immune system. The digestive tract can be infected by bacteria or viruses that can provoke an immune response. In the process of creating an immune response against the invaders, the digestive tract becomes inflamed.

In a healthy immune response, inflammation ends when the infection ends. In people with IBD, however, inflammation of the digestive tract may occur even without an infection. This is because their immune systems attack their own tissues. This is known as an autoimmune reaction.

Additionally, IBD can occur if the inflammation doesn’t subside after an infection is cured. The inflammation can last for months or even years.


Crohn’s disease is strongly linked to smoking. Crohn’s disease sufferers are also more likely to experience pain and other symptoms if they smoke. Additionally, it increases the likelihood of complications.

In contrast, UC primarily affects non-smokers and ex-smokers.


Despite the fact that IBD can occur at any age, it usually begins before the age of 35.

Environmental factors

Research suggests that people who live in urban areas and industrialized countries are more likely to develop IBD. In industrialized countries, people tend to consume a lot of fat and processed foods.

People living in northern climates, where it is often cold, are also more likely to suffer from IBD.

In an analysis of the impact of environmental factors on IBD, researchers found that having a sedentary job or lifestyle also increases your risk for IBD.

Some studies, including one conducted in 2013, have found that physical activity during the pre-illness period may help to reduce the risk of developing IBD. For Crohn’s disease, a greater reduction was observed than for UC.


Women and men tend to suffer from IBD equally.

According to a study published in 2018, UC tends to affect more men over 45 than women in the same age group.

Crohn’s disease, on the other hand, is more common in girls and women over the age of 14.

Symptoms of IBD

According to the severity and location of inflammation, IBD symptoms may include:

  • diarrhoea, a condition in which the bowel cannot reabsorb water
  • bleeding ulcers, a condition that can cause blood to appear in the stool (hematochezia)
  • abdominal pain, cramping, and bloating caused by bowel obstruction
  • Loss of weight or anemia, which can cause children’s physical development to suffer

It is also possible for Crohn’s disease patients to suffer from canker sores in their mouths. There is also the possibility of ulcers and fissures in the genital region and anus.

There can also be problems outside of the digestive system that are associated with IBD, such as:

  • inflamed eyes
  • skin conditions
  • arthritis

Possible complications of IBD:

Among the possible complications of IBD are:

  • weight loss due to malnutrition
  • colorectal cancer
  • fistulas, or tunnels that go through the bowel wall, creating a hole between different parts of the digestive tract
  • intestinal rupture, which is also known as perforation
  • obstruction of the bowel

In rare instances, IBD flare-ups can result in shock, which is potentially life-threatening. During an episode of bloody diarrhoea, shock is usually caused by the loss of blood from the body.

How is IBD diagnosed?

Your doctor will ask you questions about your family’s medical history and about your bowel movements before diagnosing IBD.

Afterward, a physical exam may be performed, followed by additional diagnostic tests.

Stool sample and blood test

Infections and other diseases can be diagnosed through stool samples and blood tests.

In some cases, blood tests can also be used to differentiate between UC and Crohn’s disease. These tests, however, cannot diagnose IBD on their own.

Barium enema

During a barium enema, X-rays are taken of the colon and small intestine. Previously, this type of test was commonly used, but other tests have largely replaced it.

Colonoscopy and flexible sigmoidoscopy

The colon is inspected using a camera attached to a thin, flexible probe.

It is inserted through the anus. It allows your doctor to examine the rectum and colon for ulcers, fistulas, and other abnormalities.

The entire length of the large intestine can be examined during a colonoscopy. A sigmoidoscopy is limited to checking the last 20 inches of the large intestine – the sigmoid colon.

It is sometimes necessary to take a sample of tissue from within the intestine during these procedures. This is known as a biopsy. A microscope can be used to examine this sample and diagnose IBD.

Capsule endoscopy

This test examines the small intestine, which is trickier to inspect than the large intestine. A small capsule containing a camera is swallowed as part of the test.

As the capsule moves through the small intestine, the camera will take pictures. Using a computer, you can view the pictures after you have passed the camera in your stool.

Tests like this one are only used when other tests have been unsuccessful in finding the source of Crohn’s disease symptoms.

Plain film or X-ray

An abdominal X-ray is taken in emergency situations where there is a possibility that an intestinal rupture has occurred.

MRI and CT scans.

A CT scan is basically a computerized X-ray. Compared to standard X-rays, the images are more detailed. Small intestines can therefore be seen more clearly. Complications associated with IBD can also be detected.

MRI images are formed using magnetic fields. They are safer than X-rays because they don’t require radiation. Soft tissues and fistulas are best examined using MRIs.

CT scans and MRIs are both useful for assessing how much of the intestine is affected by IBD.

Treating inflammatory bowel disease

IBD can be treated in a variety of ways.


The first step in treating IBD is anti-inflammatory medications. They assist in reducing inflammation in the digestive tract. Unfortunately, they have many side effects.


Glucocorticoids, in the form of corticosteroids, are an example of anti-inflammatory drugs used for IBD. Examples include:

  • budesonide (Uceris)
  • prednisone (Prednisone Intensol, Rayos)
  • prednisolone (Millipred, Prelone)
  • methylprednisolone (Medrol, Depo-Medrol)

From oral tablets to injections and rectal foams, these medications come in many forms. Generally, they’re given in the lowest possible dose for the shortest amount of time.

5-ASA drugs (aminosalicylates)

5-ASA drugs (aminosalicylates) also decrease inflammation, mainly in the colon and the last part of the small intestine. These drugs include:

  • balsalazide (Colazal)
  • mesalamine (Apriso, Asacol HD, Canasa, Pentasa)
  • olsalazine (Dipentum), which is only available as a brand-name drug
  • sulfasalazine (Azulfidine)

An official treatment guideline from the American Gastroenterological Association (AGA) for mild to moderate UC in adults was released in 2019. Their recommendations were:

  • standard-dose oral mesalamine
  • diazo-bonded 5-ASA drugs, such as balsalazide and olsalazine

The treatment is preferred over low-dose mesalamine, sulfasalazine, or no treatment. It’s okay to take sulfasalazine, as long as you’re aware that it comes with more side effects, says the AGA.

Those who do not respond to standard-dose mesalamine or diazo-bonded 5-ASA drugs should try a combination of rectal mesalamine and high-dose oral mesalamine.


When corticosteroids and 5-ASA drugs aren’t enough, immunomodulators may be an option. This type of drug prevents the immune system from attacking the bowel and causing inflammation.

These include:

  • methotrexate (Otrexup, Trexall, Rasuvo)
  • azathioprine (Azasan, Imuran)
  • mercaptopurine (Purixan)

These drugs have not been approved by the Food and Drug Administration (FDA) to treat IBD. Still, it’s possible your doctor will prescribe them. This is known as off-label drug use.


Off-label drug use occurs when a drug that is approved by the Food and Drug Administration (FDA) for one purpose is used for a different purpose.

Doctors can nevertheless use these drugs for that purpose. FDA regulations apply to testing and approval of drugs, but not to the way doctors use drugs to treat patients’ medical conditions.

Consequently, your doctor can prescribe a drug however they deem appropriate for your treatment.


Patients with moderate to severe IBD may benefit from biologics, which are genetically designed drugs.

TNF (tumor necrosis factor) can be blocked by certain biologics. Inflammation is caused by TNF, a chemical produced by the immune system. In normal circumstances, excess TNF in the blood is blocked, but in people with IBD, higher levels of TNF can contribute to more inflammation.

Among the TNF-alpha inhibitors are:

  • adalimumab (Humira)
  • golimumab (Simponi)
  • infliximab (Remicade)

Other biologics include:

  • certolizumab (Cimzia)
  • natalizumab (Tysabri)
  • ustekinumab (Stelara)
  • vedolizumab (Entyvio)

Drugs that are biologics cannot be purchased as generics. Some of these drugs are available as biosimilars, which are cheaper and reverse engineered to produce the same results as biologics.

The AGA released treatment guidelines in 2020 for people with moderate to severe UC. For people who have never tried a biologic before, they recommend infliximab or vedolizumab over adalimumab. The latter is less effective.

It is possible to self-administer adalimumab, which may make it more convenient than the other drugs. It’s fine to choose adalimumab if convenience is a concern.

Other medications

Tofacitinib (Xeljanz) blocks a different pathway causing inflammation, also used by UC patients. The AGA recommends that this oral drug be taken only as part of a clinical trial or registry study due to safety concerns.

Antibiotics are used to kill bacteria that can trigger or worsen Crohn’s symptoms.

IBD symptoms can also be treated with antidiarrheal medications and laxatives.

Lifestyle choices

When you have IBD, lifestyle choices are crucial.

By drinking plenty of fluids, you can replace those lost in your stool. Cutting out dairy products and maintaining a stress-free environment will also help improve symptoms.

Exercise and quitting smoking can help you improve your health further.


Supplementing with vitamins and minerals can help overcome nutritional deficiencies. Iron supplements, for example, can help treat anaemia.

Before supplementing your diet with new supplements, seek the advice of your doctor.


IBD patients sometimes require surgery. IBD surgeries include the following:

  • Widening a narrowed bowel with a strictureplasty
  • Fistula closure or removal
  • Surgical removal of affected parts of the intestines in people with Crohn’s disease
  • For severe cases of UC, the entire colon and rectum are removed

Those with IBD are at a higher risk for colorectal cancer, so routine colonoscopy helps detect it early.

What can be done to prevent IBD?

Hereditary causes of IBD cannot be prevented. You can reduce your risk of developing IBD or preventing a relapse, however, if you take the following steps:

  • Consuming nutrient-rich foods
  • along with regular exercise
  • as well as quitting smoking

Although IBD can cause discomfort, there are ways you can manage the disease and still lead an active, healthy life.

Speaking with others who understand what you’re going through can also be helpful.