Gastrointestinal (GI) disease encompasses many different types of disorders and can affect any part of the digestive tract, which includes the entire system from the mouth to the anus. Some GI disorders are minor and transitory, while others can be severe and/or chronic. Doctors perform many different types of tests to diagnose the source of GI symptoms. Which is chosen depends on the symptoms that are presenting, the specific health risks of the individual patient, and their health history. In this two-part series, we’ll provide an overview of GI disorders and explore a few common types, including their symptoms, diagnosis, and treatment.