Duodenitis: A Guide to Causes, Treatments, and Prevention

Medically Reviewed By Saurabh Sethi, M.D., MPH
Was this helpful?

Duodenitis is inflammation in the duodenum, the first part of the small intestine. It can cause abdominal pain, bleeding, and other digestive symptoms. Causes of duodenitis include infections, medicines, and alcohol or tobacco use. For certain infections, antibiotics can successfully treat duodenitis. When an infection is not the cause, medicines that reduce stomach acid can be an effective duodenitis treatment. Lifestyle changes, such as limiting alcohol and tobacco use, can reduce your risk of duodenitis.

This article explains duodenitis and its causes, symptoms, and treatments.

What is duodenitis?

Woman resting on a bed with hand on upper abdomen
Studio Firma/Stocksy United

Duodenitis is inflammation of the upper small intestine. This section connects to the stomach. Stomach conditions and diseases can also affect the duodenum.

The most common cause of duodenitis is a stomach infection with the bacteria Helicobacter pylori (H. pylori). This bacteria also causes inflammation of the stomach, or gastritis. Thus, gastritis is closely related to duodenitis. They share many of the same causes, symptoms, and treatments.

If you have duodenitis, your disease course may vary from other people’s. The signs and symptoms can be constant or may come and go. Some people with duodenitis have no symptoms at all. Others may have burning pain or nausea with or without vomiting. 

See your doctor if you have symptoms of duodenitis. Seek immediate medical care (call 911) for serious symptoms such as severe abdominal pain, bloody or black tarry stools, or bloody or black vomit.

What causes duodenitis?

The most common cause of both gastritis and duodenitis is infection with H. pyloriH. pylori disrupts the mucus barrier that normally protects the delicate duodenal lining.

Loss of this barrier allows acidic stomach contents to irritate the lining. This puts a person at risk of chronic inflammation and duodenal ulcer. Nonsteroidal anti-inflammatory drugs (NSAIDs) have a similar effect.

Many people get an H. pylori infection at a young age. However, symptoms commonly do not appear until adulthood. If H. pylori is the cause of duodenitis, symptoms will continue until you treat the infection.

Other less common causes of duodenitis include:

  • Autoimmune diseases: These include autoimmune enteropathy and Celiac disease, which attack the lining of the intestines.
  • Cancer treatments: Chemotherapy and radiation therapy can cause duodenitis.
  • Critical illness: A critical illness can decrease blood flow to the digestive system, causing stress and disruption of the lining.
  • Crohn’s disease: This is a form of inflammatory bowel disease that can affect the small intestine.
  • Food allergies: Allergies to milk and soy, among others, can cause duodenitis.
  • Graft versus host disease: This is a condition that can develop after a donor transplant.
  • Malabsorption diseases: These include tropical sprue, a chronic diarrheal disease.
  • Medications: NSAIDs such as ibuprofen (Advil, Motrin), naproxen (Aleve), and aspirin can cause duodenitis.
  • Peptic duodenitis: This is a condition in which there is excess stomach acid production.
  • Substance use: Substances such as alcohol and tobacco in prolonged or excessive use can cause duodenitis.

What are the symptoms of duodenitis?

Duodenitis may result in a number of symptoms. The intensity of symptoms can vary among individuals.

Common symptoms of duodenitis

You may get duodenitis symptoms daily or just once in a while. At times, any of these symptoms can be severe, including:

Diagnosing and treating duodenitis

Treatment for duodenitis begins with diagnosing it. To find out whether you have duodenitis, your doctor may order blood, urine, and stool samples for laboratory tests.

Imaging exams, such as an upper endoscopy to look at the lining of duodenum, may be necessary.

During an endoscopy, doctors can take small mucosal biopsies. Biopsies can confirm whether you have an H. pylori infection.

A complete diagnosis will guide your treatment, which may include antibiotics and medicine to reduce stomach acid.


When duodenitis is due to an H. pylori infection, triple therapy is standard treatment. This consists of two antibiotics and a proton pump inhibitor (PPI). The most common antibiotics for H. pylori include:

  • amoxicillin
  • clarithromycin (Biaxin)
  • metronidazole (Flagyl)
  • tetracycline

Treatment with triple therapy lasts for 14–21 days. It is important to follow your antibiotic treatment plan precisely to avoid reinfection or recurrence. 

Proton pump inhibitors

PPIs decrease stomach acid production. They are part of triple therapy for H. pylori. They may also be effective for other causes of duodenitis. PPIs include:

  • esomeprazole (Nexium)
  • lansoprazole (Prevacid)
  • omeprazole (Prilosec)
  • pantoprazole (Protonix)
  • rabeprazole (Aciphex)

Histamine H2-receptor antagonists

Histamine H2-receptor antagonists also decrease the amount of acid in the stomach. These drugs include:

  • cimetidine (Tagamet)
  • famotidine (Pepcid)
  • nizatidine (Axid)

If you have diarrhea or vomiting from duodenitis, fluid and electrolyte replacement is also a component of successful treatment.

Lifestyle considerations for duodenitis

You may help reduce your risk of H. pylori infection with certain hygiene practices. This includes washing your hands with soap and water. Hand washing is especially important when you are preparing food.

Increasing your intake of cruciferous vegetables may also help prevent infection. These vegetables include broccoli, cabbage, and cauliflower.

Limiting alcohol intake, tobacco use, and use of NSAIDs can also reduce your risk of duodenitis. It may also help to avoid foods that can irritate the lining of the digestive tract, such as spicy foods.

What are the potential complications of duodenitis?

Potential complications of duodenitis include:

You can help reduce the risk of serious complications by following your treatment plan. 


Duodenitis is inflammation of the first part of the small intestine. It is closely related to gastritis, which is inflammation of the stomach. The two conditions are most commonly the result of an H. pylori infection.

You can have this infection for years and not know about it until it causes problems. Treating it involves triple therapy with two antibiotics and a PPI. Treatment often helps symptoms, but recurrences are common.

Was this helpful?
Medical Reviewer: Saurabh Sethi, M.D., MPH
Last Review Date: 2022 Mar 28
View All Digestive Health Articles
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.