# Best Gastroenterologists in Missouri (October 2026)

Updated October 2026. Source: https://bestdocs.us/missouri/gastroenterologists/

Dr. Ruben Aymerich ranks first with a score of 88.7: 5.0 stars from 646 Google reviews; 30 years since medical school; accepts Medicare assignment. Dr. Jeffrey Mathews ranks second with a score of 88.0: 5.0 stars from 448 Google reviews; 38 years since medical school; accepts Medicare assignment. Dr. Richard Riegel ranks third with a score of 88.0: 5.0 stars from 440 Google reviews; 35 years since medical school; accepts Medicare assignment.

1. **Ruben Aymerich, MD** — Gastroenterologist, St. Louis, MO. Score 88.7. Google 5.0 from 646 reviews; 30 years since medical school; accepts Medicare assignment; enrolled in Missouri Medicaid. [Profile](https://bestdocs.us/doctor/ruben-aymerich-gastroenterologist-st-louis-1609858562/)
2. **Jeffrey Mathews, MD** — Gastroenterologist, Chesterfield, MO. Score 88.0. Google 5.0 from 448 reviews; 38 years since medical school; accepts Medicare assignment. [Profile](https://bestdocs.us/doctor/jeffrey-mathews-gastroenterologist-chesterfield-1285635656/)
3. **Richard Riegel, MD** — Gastroenterologist, Chesterfield, MO. Score 88.0. Google 5.0 from 440 reviews; 35 years since medical school; accepts Medicare assignment. [Profile](https://bestdocs.us/doctor/richard-riegel-gastroenterologist-chesterfield-1669472700/)
4. **Brian McMorrow, MD** — Gastroenterologist, Chesterfield, MO. Score 86.9. Google 5.0 from 296 reviews; 34 years since medical school; accepts Medicare assignment. [Profile](https://bestdocs.us/doctor/brian-mcmorrow-gastroenterologist-chesterfield-1851391890/)
5. **Joel Riley, MD** — Gastroenterologist, St. Louis, MO. Score 86.4. Google 4.9 from 1,266 reviews; 40 years since medical school; accepts Medicare assignment; enrolled in Missouri Medicaid. [Profile](https://bestdocs.us/doctor/joel-riley-gastroenterologist-st-louis-1164440301/)
6. **Leonard Weinstock, MD** — Gastroenterologist, Creve Coeur, MO. Score 85.6. Google 4.9 from 624 reviews; 45 years since medical school; accepts Medicare assignment; enrolled in Missouri Medicaid. [Profile](https://bestdocs.us/doctor/leonard-weinstock-gastroenterologist-creve-coeur-1467566703/)
7. **Marc Taormina, MD** — Gastroenterologist, Lees Summit, MO. Score 85.4. Google 4.9 from 547 reviews; 50 years since medical school; accepts Medicare assignment; enrolled in Missouri Medicaid. [Profile](https://bestdocs.us/doctor/marc-taormina-gastroenterologist-lees-summit-1992788038/)
8. **Erik Thyssen, MD** — Gastroenterologist, Creve Coeur, MO. Score 85.4. Google 4.9 from 534 reviews; 42 years since medical school; accepts Medicare assignment; enrolled in Missouri Medicaid. [Profile](https://bestdocs.us/doctor/erik-thyssen-gastroenterologist-creve-coeur-1750495099/)
9. **Thomas Jones, MD** — Gastroenterologist, Liberty, MO. Score 84.4. Google 4.9 from 330 reviews; 38 years since medical school; accepts Medicare assignment; enrolled in Missouri Medicaid. [Profile](https://bestdocs.us/doctor/thomas-jones-gastroenterologist-liberty-1740283753/)
10. **Fred Williams, MD** — Gastroenterologist, Chesterfield, MO. Score 84.2. Google 5.0 from 148 reviews; 40 years since medical school; accepts Medicare assignment. [Profile](https://bestdocs.us/doctor/fred-williams-gastroenterologist-chesterfield-1386644326/)

Ranked by the BestDocs score (https://bestdocs.us/methodology/), weighted toward independent third-party verified patient reviews (60%) over public anonymous reviews (40%). Sponsored placements never change rank.