Dr. Rosenthal has been with West Gastroenterology Medical Group since March of 2004. Dr. Rosenthal is currently a retired per diem Gastroenterologist for the Kaiser Foundation Hospital, West Los Angeles. Dr. Rosenthal has held positions as Chairman of Regional Gastroenterology Committee for Southern California Permanente, Chief Physician of Gastroenterology Section for Kaiser West Los Angeles, and past President of the Southern California Society for Gastrointestinal Endoscopy. Dr. Rosenthal is currently an Assistant Clinical Professor for UCLA’s Department of Medicine, and has been an attending physician in Gastroenterology at UCLA-Wadsworth VA Hospital since 1971. Dr. Rosenthal became a Diplomat of the American Board of Internal Medicine in 1972 and a Diplomat of the American Board of Gastroenterology in 1975. Dr. Rosenthal is a member of the Southern California Society for Gastrointestinal Endoscopy, Southern California Society for Gastroenterology, American Gastroenterological Association, and American Society of Gastrointestinal Endoscopy.