Dr. Donald Castell is a 1960 graduate of the George Washington University School of Medicine, and served as a medical officer in the U.S. Navy from 1959 to 1979. Before retiring with the rank of captain, he spent his last four years of active service as chairman of medicine at the National Naval Medical Center in Bethesda, Maryland. He has held faculty positions at George Washington University School of Medicine, the Uniformed Services University of the Health Sciences, Bowman Gray School of Medicine in Winston-Salem, North Carolina, and Jefferson Medical College in Philadelphia. From April 1992 to September 2001, he was the Kimbel Professor and chairman of the department of medicine at Graduate Hospital in Philadelphia, as well as professor of medicine. In October 2001, Dr. Castell joined the faculty of the Medical University of South Carolina in Charleston, where he is professor of medicine and director of the Esophageal Disorders Program.

Dr. Castell is internationally recognized as a leading authority on diseases of the esophagus and esophageal function, and has authored or co-authored more than 500 scientific publications. He is also the editor of and principal contributor to The Esophagus, the primary text on this subject, a definitive 714-page text published by Little, Brown, and Company, now in its fourth edition, which came out in 2004. He was president of the American Gastroenterological Association from 1998 to 1999.