Gregory L. Shannon, MD, is a board-certified gastroenterologist providing comprehensive care for adults with conditions affecting the digestive system. Practicing in Sugar Land, Texas, he evaluates and treats a broad range of gastrointestinal concerns involving the esophagus, stomach, intestines, colon, liver, biliary system, and pancreas. With over 30 years of experience in gastroenterology, Dr. Shannon brings extensive clinical experience to the evaluation and management of both common digestive problems and chronic gastrointestinal conditions.

Dr. Shannon earned his medical degree from Northwestern University Feinberg School of Medicine in 1996. He completed his Internal Medicine residency at Baylor College of Medicine from 1996 to 1999, followed by fellowship training in Gastroenterology at Baylor College of Medicine from 1999 to 2002. He is board certified in Gastroenterology by the American Board of Internal Medicine.

His clinical interests include colon cancer prevention, colon polyps, Crohn’s disease, and ulcerative colitis. His practice also encompasses conditions such as gastroesophageal reflux disease, diverticular disease, hemorrhoids, esophagitis, gastrointestinal bleeding, peptic ulcers, and other disorders affecting the digestive tract. These conditions may present with symptoms ranging from abdominal discomfort and changes in bowel habits to reflux, bleeding, or difficulty swallowing, making careful evaluation an important part of determining appropriate care.

Dr. Shannon provides diagnostic and endoscopic care when appropriate with procedures including colonoscopy, lower gastrointestinal endoscopy, upper gastrointestinal endoscopy, flexible sigmoidoscopy, and esophageal dilation, among other diagnostic procedures. Colonoscopy plays an important role in colorectal cancer screening and the evaluation and management of colon polyps, while upper endoscopy can help investigate conditions affecting the esophagus, stomach, and upper digestive tract.

In addition to his clinical practice, Dr. Shannon participates in clinical research and is a Principal Investigator in Gastroenterology with R&H Clinical Research. He practices through Gastroenterology Associates of Texas and is affiliated with Memorial Hermann Sugar Land Hospital. His approach to care emphasizes listening to patients, understanding their concerns, explaining findings clearly, and developing an appropriate plan based on their individual clinical needs.