Gary Koenig, M.D.
NPI 1861485724 · Gastroenterology Physician · Hazelwood, MO
Enrolled with Medicare as Practitioner - Gastroenterology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gary Koenig, M.D. is a Gastroenterology Physician provider in Hazelwood, MO (NPI 1861485724).
Provider details
- NPI number
- 1861485724
- Entity type
- Individual
- Primary specialty
- Gastroenterology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Male
- Sole proprietor
- Yes
- License
- MDR3G44 (MO)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
319 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 46 | $126 |
| Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43239 | 45 | $94 |
| Removal of Polyps Or Growths of Large Bowel Using an Endoscope With Mechanical Snare45385 | 36 | $238 |
| Colorectal Cancer Screening; Colonoscopy on Individual Not Meeting Criteria for High RiskG0121 | 34 | $171 |
| Biopsy of Large Bowel Using a Flexible Endoscope45380 | 32 | $147 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 20 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Peg3350/Sod Sulf,bicarb,cl/Kclbrand: Gavilyte-G | 375 | 365 |
| Sodium, Potassium,mag Sulfatesbrand: Sod Sulf-Potass Sulf-Mag Sulf | 290 | 281 |
| Omeprazole | 192 | 74 |
| Pantoprazole Sodium | 63 | 23 |
| Peg3350/Sod Sulf,bicarb,cl/Kclbrand: Gavilyte-C | 55 | 55 |
| Linaclotidebrand: Linzess | 49 | 13 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$3,396 across 185 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 20 Progress Point Pkwy Ste 206O Fallon, MO 63368-2207Phone: (636) 344-1073Fax: (636) 916-9953
Registry dates
- Enumerated
- 2005-08-25
- Last updated
- 2026-02-16
- Certified
- 2026-02-16
Frequently asked questions
- What is Gary Koenig's NPI number?
- Gary Koenig's National Provider Identifier (NPI) is 1861485724, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gary Koenig's specialty?
- Gary Koenig is listed in the NPPES registry with a primary specialty of Gastroenterology Physician (Allopathic & Osteopathic Physicians).
- Where is Gary Koenig located?
- Gary Koenig's practice location on file with NPPES is 100 Village Sq, Hazelwood, MO 63042-1820.
- What is Gary Koenig's phone number?
- The practice phone number listed in the NPPES registry for Gary Koenig is (314) 355-4010.
- Does Gary Koenig accept Medicare?
- Gary Koenig is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gary Koenig's NPI active?
- Yes — Gary Koenig's NPI (1861485724) is active in the NPPES registry as of the last update on 2026-02-16.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.