Some common causes of an inflamed esophagus are reflux of acidic stomach contents, the effects of some medications, and bacterial or viral infections, according to Healthline. In children, an allergic reaction known as eosinophilic esophagitis, which results from too many white blood cells in the esophagus, is a common cause of esophageal inflammation as well. Some foods that trigger this condition in susceptible children are milk, soy, eggs, rye and wheat. Peanuts and beef are also potential triggers.
The most common cause of esophageal inflammation due to reflux is gastroesophageal reflux disease, or GERD, states Healthline. A chronic condition, GERD is often the result of a defect in the lower esophageal sphincter, a ring of muscle located at the end of the esophagus where it joins the stomach, states MedicineNet. When this sphincter functions normally, it opens when a person swallows but stays closed at other times, keeping stomach contents in place. When it is not working properly, stomach contents may back up and irritate the esophagus. Hiatal hernias, which occur when a small portion of the stomach pushes up through the diaphragm, and abnormally slow emptying of the stomach often contribute to GERD.
Medications that irritate the esophagus include pain relievers, such as ibuprofen and naproxen, potassium chloride, antibiotics, and medicines that prevent bone loss. Taking medicines with too little water often contributes to this problem, Mayo Clinic warns. Infections of the esophagus are relatively rare, and occur most often in people with compromised immune systems, such as those with HIV/AIDS or cancer.