Esophagitis is the inflammation or irritation of the esophagus. The major types of esophagitis are medication-induced, infectious, eosinophilic, corrosive, and acid reflux. Patients typically present with odynophagia, dysphagia, and retrosternal chest pain. Diagnosis is by endoscopy and biopsy. Laboratory tests and imaging are obtained, depending on the degree of damage and involvement of other organ systems. Treatment for esophagitis depends on the underlying etiology and includes dietary changes, avoidance of offending agents, antibiotic therapy, or proton pump inhibitor use. In severe cases such as in corrosive injury, surgery may need to be performed. If left untreated, esophagitis can lead to complications such as strictures, metaplasia of the esophagus, and development of malignancy.