What is enteritis?everything you need to know

Inflammation of the small intestine called enteritis. Inflammation (redness and swelling) can be caused by infection, certain medications, radiation therapy, or chronic medical conditions such as Crohn’s disease or celiac disease. Symptoms may include pain, diarrhea, vomiting, and blood in the stool.


Enteritis can be caused by a range of diseases or medications that affect the small intestine. In some cases, enteritis can be caused by eating or drinking something contaminated with bacteria or viruses. Radiation therapy for cancer can also cause inflammation of the digestive system.

Some causes of enteritis are:

  • Bacterial infections
  • Celiac disease (an autoimmune disease in which your white blood cells attack your intestinal lining after exposure to gluten)
  • Crohn’s disease (an inflammatory bowel disease)
  • NSAIDs (NSAIDs, including ibuprofen Aleve and Motrin and naproxen Aleve)
  • Radiation Therapy
  • Viral infection
  • Whipple disease (a rare bacterial infection that causes difficulty breaking down fat in the digestive tract)

Types of

The type of enteritis depends on the cause of the inflammation. The more common causes include food poisoning and radiation enteritis.

Infectious enteritis (food poisoning)

Food poisoning that occurs after eating or drinking food contaminated with viruses or bacteria can cause enteritis.


There are an estimated 48 million incidents of food poisoning in the United States each year.

If food is undercooked or stored improperly, it can become contaminated. Food poisoning can also occur when food comes into contact with water or utensils that have not been properly cleaned after being contaminated with viruses or bacteria.

Contamination can also occur if food is prepared by someone who does not wash their hands properly after using the bathroom or before starting to cook.

radiation enteritis

Radiation therapy treats various forms of cancer. High doses of radiation are directed at cancer cells to shrink or kill them and stop the cancer from spreading to other parts of the body.

The risk of radiation enteritis increases with higher doses of radiation, large treatment areas, previous abdominal surgery, or a diagnosis of diabetes (a chronic disease that affects how your body uses blood sugar or glucose) or high blood pressure (hypertension). Irradiating much of the gut is also thought to increase risk.


For those receiving radiation therapy to the abdomen or pelvis, up to 90 percent experience changes in bowel habits. It is estimated that about 15% of people will have chronic problems.

Radiation therapy for cancers that develop in the pelvis, abdomen, or colon can cause radiation enteritis. This is usually an acute (short-term) problem, but can also become a chronic (long-term) problem.


Symptoms of acute enteritis may include:

  • stomach ache
  • bloating
  • diarrhea (sometimes with blood or mucus)
  • fatigue
  • nausea
  • urgency

If radiation enteritis becomes chronic, it may also cause the following signs and symptoms:

  • Intestinal obstruction (blockage in the bowel)
  • chronic abdominal pain
  • Malabsorption (absorption of malnutrition from food)
  • Bowel perforation (hole in the intestine)
  • lose weight

side effect

Sometimes symptoms of enteritis can lead to complications both inside and outside the digestive system.


There are several different types of anemia, and it has many causes. anemia is when the blood lacks healthy red blood cells to deliver enough oxygen to the cells of the body.

In some cases of enteritis, intestinal bleeding can be a problem. Bleeding may be enough to cause anemia.

Symptoms of anemia may include:

  • Dizziness
  • fatigue
  • headache
  • arrhythmia
  • shortness of breath

Treatment of anemia may include taking iron or vitamin supplements, or, in more severe cases, intravenous iron or blood transfusions.


Diarrhea (watery stools) can lead to dehydration. dehydration Refers to the loss of excess fluid from the body (such as through diarrhea and/or vomiting), which is not replaced by drinking alcohol.

Symptoms of dehydration may include:

  • chapped lips
  • dry eyes
  • dry mouth
  • feeling thirsty
  • headache
  • Insufficient urination
  • muscle spasms

partial bowel obstruction

One of the potentially more serious complications of enteritis is bowel obstruction. Obstruction is when the bowel begins to close on its own, which is called a stricture. As the intestine narrows, food and stool cannot pass through it freely, and it can become blocked.

Bowel obstruction may be partial or total. In some cases, enteritis is found because an obstruction has occurred. Partial obstructions can be managed conservatively with bowel decompression (a tube inserted through the nose and suctioned for a few days). Others may require surgery to resolve.


For radiation enteritis, the team providing treatment will take steps to prevent it. Using the lowest possible dose in the smallest abdomen is important for prevention. Bladder filling may also be helpful during treatment, and the radiology team will implement more technical work.

To avoid enteritis caused by food poisoning, it is important to:

  • Keep utensils, cooking surfaces, fruits and vegetables clean.
  • Keep food hot after it is cooked.
  • Put food in the refrigerator immediately.
  • Separate raw meat and poultry from other foods.
  • Wash your hands often, especially before cooking.
  • Do not drink untreated water from streams, lakes, rivers and other bodies of water.
  • Avoid drinking tap water when traveling to areas where the water causes bacterial infections.

Food Safety and How to Prevent Food Poisoning


Treatment for radiation enteritis usually focuses on symptoms. Diarrhea can be treated with antidiarrheal medicines. In cases of dehydration or malnutrition, fluids and nutrients can be given through an intravenous (IV) line. Other types of medications, such as anti-inflammatory drugs, antibiotics, or steroids, may also be used.

Further advice may include drinking plenty of water, eating a low-fiber diet and eating small meals several times a day. Probiotics (good gut bacteria) or prebiotics (nutrients that promote healthy gut bacteria) are being studied as a treatment and may also be recommended by doctors.

In acute cases of radiation enteritis, the lining of the small intestine may return to normal over time, which may take about six months.

In the case of an infection, most of the time people get better on their own without any treatment. It is generally recommended to drink plenty of fluids and replace electrolytes (salts in the blood) by drinking sports drinks or broth.

Medications to slow diarrhea may also be recommended. It is important to speak with a healthcare provider before using them. Antidiarrheal medicines may not help if you have blood in your stool or a bacterial infection.

When to get immediate care

Seek immediate medical attention if you experience the following symptoms:

  • blood in stool
  • diarrhea that won’t stop
  • dizziness or fainting
  • lethargy or extreme fatigue
  • severe or sudden abdominal pain
  • vomiting


Enteritis is when the small intestine becomes irritated and inflamed. This can cause symptoms such as diarrhea, vomiting, and blood in the stool. Treatment may include dietary changes, medication, and more fluid intake.

VigorTip words

Enteritis can cause many uncomfortable symptoms. Special care is needed to avoid infection-causing bacteria when cooking and handling food and when traveling.

Radiation enteritis may be harder to avoid for people with certain types of cancer, but steps can be taken to lessen the effects of radiation. Discussing symptoms, especially blood in the stool, with a healthcare provider is important to understand the cause and get treatment.

Frequently Asked Questions

  • How long will enteritis last?

    Enteritis can last from days (caused by infection) to months (caused by radiation therapy). In the case of chronic enteritis, it may last longer.

  • Can enteritis be cured?

    Yes. Enteritis caused by an infection may go away on its own with home treatment alone. In the case of radiation enteritis, most cases are treatable. Some people may develop chronic enteritis, which may persist and require more intensive treatment.

  • How to perform a gastroenteritis test?

    Blood and stool tests can be used to confirm or rule out colitis caused by infection. However, food poisoning is usually diagnosed based on symptoms.

    When symptoms become worrisome, it may be necessary to get tested to see what’s causing them. Imaging tests, such as computed tomography (CT), which uses X-rays to get detailed images, or magnetic resonance enema (MRE), which uses magnetic fields, may be helpful.

    Endoscopy can also be used, using a thin tube with a camera and a light on the end to look inside the digestive system. A test in which a patient swallows a pill with a camera attached is called a small bowel capsule endoscopy and is sometimes used for diagnosis.