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Doctors / MO

GARY D KOENIG, MD

GASTROENTEROLOGY

Medical school: SAINT LOUIS UNIVERSITY SCHOOL OF MEDICINE

Graduated: 1986

Also: INTERNAL MEDICINE

NPI: 1861485724

Practice Locations (3)

PHYSICIAN GROUPS LC

2630 HWY K

O FALLON, MO 633686624

6362405454

PHYSICIAN GROUPS LC

10 HOSPITAL DR, SUITE 100

SAINT PETERS, MO 633761659

6369167272

MERCY CLINIC GASTROENTEROLOGY LLC

901 PATIENTS 1ST DR, SUITE 3300

WASHINGTON, MO 630904700

6362397344

Source: CMS National Downloadable File, September 2026.

GARY KOENIG, MD | HealthCareAtlasUSA