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Gastroenterologist

Supannee Rassameehiran, M.D.

Dr. Supannee Rassameehiran is an accomplished gastroenterologist with advanced training in hepatology and liver transplantation. She completed her medical education at Mahidol University in Thailand and has since held fellowships at Baylor College of Medicine and the Medical College of Georgia at Augusta University. Dr. Rassameehiran traveled to Guam and is currently practicing at Guam Regional Medical City, where she is one of only two gastroenterologists on the island. She specializes in gastroenterology, with a particular focus on liver diseases and liver transplantation. Dr. Rassameehiran is recognized for her extensive research contributions, having authored numerous peer-reviewed publications, and delivered multiple presentations at national medical conferences.

  • English and Thai
  • 671-633-GRMC
  • refer@grmc.gu

Specialty

Gastroenterology

Board Certifications

• American Board of Gastroenterology • American Board of Internal Medicine

Medical Licensures

  • Washington
  • Georgia
  • Texas

Conditions

• Bleeding from GI tract. • Gastrointestinal (GI) Motility Disorders, such as gastroparesis, chronic abdominal pain, functional dyspepsia, constipation, and diarrhea. • Small Bowel Disorders: Celiac disease, small bowel bacterial overgrowth (SIBO), Crohn’s disease, and intestinal malabsorption. • Hepatobiliary disease assessments: Liver enzyme abnormalities, viral hepatitis, hepatitis, including autoimmune hepatitis cirrhosis, and hepatocellular carcinoma. • Esophageal Disorders: GERD, Barrett’s esophagus, esophageal varices, dysphagia, and odynophagia. • GI Cancers and Cancer Screening: Colorectal polyps, suspected or diagnosed gastric, esophageal, pancreatic, colon, and rectal cancers. • Fecal Incontinence: Evaluation and management of bowel control issues and fecal incontinence. • Helicobacter Pylori Infections: Diagnosis and treatment of H. pylori infections that may lead to peptic ulcers and gastritis. • Chronic Pancreatitis: Evaluation and management of pancreatic insufficiency, pancreatic cysts, and chronic pancreatitis. • Endoscopic Procedures: For upper endoscopy (EGD), colonoscopy, sigmoidoscopy, and ERCP (endoscopic retrograde cholangiopancreatography).

Professional Associations

  • American Society for Gastrointestinal Endoscopy
  • American Association for the Study of Liver Diseases
  • American College of Gastroenterology
  • The Medical Council of Thailand

Hobbies

Hiking and traveling

Biography

Dr. Supannee Rassameehiran is a skilled gastroenterologist with specialized training in hepatology and liver transplantation. She earned her Medical Doctorate from Mahidol University’s Faculty of Medicine at the Siriraj Hospital in Thailand. Dr. Rassameehiran furthered her expertise through fellowship programs in Hepatology and Liver Transplantation at Baylor College of Medicine in Houston, Texas, followed by a gastroenterology fellowship at the Medical College of Georgia at Augusta University, where she served as Co-Chief Fellow.

Prior to her move to Guam, Dr. Rassameehiran practiced at MultiCare Yakima Memorial Hospital in Yakima, Washington, where she served as a Gastroenterology Hospitalist and managed an outpatient clinic. Her professional expertise spans the management of a wide range of gastrointestinal disorders, including GERD, irritable bowel syndrome, peptic ulcer disease, diarrhea, constipation, inflammatory bowel disease, and complex liver conditions. Dr. Rassameehiran’s extensive research experience is reflected in numerous peer-reviewed publications, with a focus on topics such as gastrointestinal bleeding, hepatocellular carcinoma, and the clinical management of cirrhosis and liver transplantation.

Throughout her career, she has received multiple awards, including Poster of Distinction at prestigious national meetings such as The Liver Meeting and Digestive Disease Week. Dr. Rassameehiran has also contributed to the medical community through a substantial number of presentations at national and regional medical conferences. Her research and clinical work have earned her recognition within the gastroenterology and hepatology communities, and she remains committed to advancing patient care and medical education in these fields.

In addition to her clinical and academic work, Dr. Rassameehiran is an active member of several prominent professional societies, including the American Society for Gastrointestinal Endoscopy, the American Association for the Study of Liver Diseases, and the American College of Gastroenterology. She is board-certified in both Internal Medicine and Gastroenterology, and holds multiple state licenses, including those in Washington, Texas, and Georgia. Her expertise and dedication to her patients make her a valuable asset to GRMC and the region.

Outside of her professional commitments, Dr. Rassameehiran enjoys hiking and traveling.

Medical School/Education

Co-Chief Fellow
Medical College of Georgia at Augusta University
Augusta, GA

Gastroenterology Fellowship
Medical College of Georgia at Augusta
Augusta, GA

Hepatology and Liver Transplantation Fellowship
Baylor College of Medicine
Houston, TX

Internal Medicine Residency
Texas Tech University Health Sciences Center
Lubbock, Texas

Medical Doctorate
Faculty of Medicine at Siriraj Hospital, Mahidol University
Thailand

Professional Experience

Gastroenterologist Hospitalist
MultiCare Yakima Memorial Hospital

Outpatient clinic
MultiCare Yakima Memorial Hospital

Gastroenterology Fellow
Medical College of Georgia at Augusta University

Hepatology and Liver Transplantation Fellow
Baylor College of Medicine

Internal Medicine Resident
Texas Tech University Health Sciences Center

PRESS RELEASE: Guam Regional Medical City Introduces Dr. Supannee “Jill” Rassameehiran | Gastroenterologist, Hepatologist

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