What is the most common cause of esophagitis?

The most common cause of esophagitis is gastroesophageal reflux disease (GERD). GERD occurs when stomach acid frequently flows back into the esophagus, leading to irritation and inflammation of the esophageal lining. The reflux of acidic gastric contents can damage the sensitive tissues of the esophagus, causing symptoms such as heartburn, regurgitation, and discomfort. This condition is prevalent in the general population and is often associated with lifestyle factors, such as obesity, diet, and certain habits.

Infection, while a significant cause of esophagitis, particularly in immunocompromised individuals, is less common in the general population. Alcohol abuse can lead to various gastrointestinal issues, but it is not the primary cause of esophagitis compared to GERD. Medications can also cause esophagitis, particularly those that are irritating to the esophagus, but this is more situational and not as widespread as the impact of GERD. Thus, GERD is widely recognized as the leading cause of esophagitis in many patients, making it the correct answer.