Duodenitis refers to inflammation of the duodenum, a part of the small intestine that is responsible for the initial breakdown of food. Synonyms for this condition include duodenal inflammation, inflammation of the first part of the small intestine, and duodenal mucosal inflammation. Other terms used to describe duodenitis may depend on the cause, such as H. pylori-induced duodenitis, reflux-induced duodenitis, or medication-induced duodenitis. Symptoms of duodenitis can include abdominal pain, bloating, nausea, and vomiting. Treatment may include medication to reduce inflammation, antibiotics to treat bacterial infections, and dietary changes. In severe cases, endoscopy or surgery may be necessary.