Guy A. Weiss, MD

Guy A. Weiss, MD

Average rating: 4.9
(92 ratings)  
Accepting new patients
Primary Location
Westwood Digestive Diseases
100 Medical Plaza
Suite 345
Los Angeles, California 90024


  • Program Leader, Celiac Disease Program

Dr. Weiss practices general gastroenterology, with particular focus on gluten-associated disorders, mainly celiac disease, non/slow-responsive celiac disease, refractory celiac disease, and non-celiac gluten sensitivity (NCGS); eosinophilic gastrointestinal disorders (EGID) including eosinophilic esophagitis (EoE), eosinophilic gastritis (EoG), eosinophilic enteritis (EoN), and eosinophilic colitis (EoC); lymphocytic gastritis; autoimmune atrophic gastritis; microscopic colitis including lymphocytic and collagenous colitis; autoimmune enteropathy; collagenous gastritis, and inflammatory bowel diseases. His research focuses on adherence to medical therapy and diet, gluten-associated disorders, and outcomes research. Dr. Weiss studied in the combined BMedSc/MD program at the Sackler School of Medicine, Tel Aviv University, Israel. He completed his internal medicine training at SUNY Buffalo, NY and served as a chief resident during his third year. He subsequently completed his gastroenterology fellowship at UCLA. During his training, Dr. Weiss developed the UCLA Celiac Collective and later joined the Westwood faculty as the UCLA Celiac Program leader. He serves on the Medical Advisory Board of the Celiac Disease Foundation and is a manuscript reviewer for journals such as Clinical Gastroenterology and Hepatology, Journal of Pediatric Gastroenterology and Nutrition, and the American Journal of Clinical Nutrition. He is the Springer/Nature editor of "Diagnosis and Management of Gluten-Associated Disorders: A Clinical Casebook."


English, Hebrew


Medical Board Certifications

Gastroenterology, American Board of Internal Medicine, 2016
Internal Medicine, American Board of Internal Medicine, 2013


Gastroenterology, UCLA School of Medicine, 2016


Internal Medicine, SUNY Health Science Center at Buffalo, 2013


Internal Medicine, SUNY Health Science Center at Buffalo, 2011


MD, Sackler School of Medicine, Tel Aviv University, 2009

Hospital Affiliations

Ronald Reagan UCLA Medical Center

Areas of Focus

General gi
Celiac disease


An update on celiac disease



  • Celiac disease
  • Eosinophilic GI disorders including eosinophilic esophagitis, microscopic colitis, autoimmune enteropathy, GERD and colorectal cancer screening
  • Non-celiac gluten sensitivity
  • Outcomes research
  • Adherence to therapy
  • Inflammatory bowel diseases (IBD)