Markham Nightengale, M. D.
NPI 1144215971 · Gastroenterology Physician · Tulsa, OK
Enrolled with Medicare as Practitioner - Gastroenterology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Provider details
- NPI number
- 1144215971
- Entity type
- Individual
- Primary specialty
- Gastroenterology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M. D.
- Sex
- Male
- Sole proprietor
- No
- License
- 18311 (OK)
Specialties & taxonomies
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
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
1,128 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) |
|---|---|---|
| Removal of Polyps Or Growths of Large Bowel Using an Endoscope With Mechanical Snare45385 | 224 | $231 |
| Biopsy of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope43239 | 175 | $48 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 157 | $118 |
| Balloon Dilation of Esophagus, Stomach, And/Or Upper Small Bowel Using a Flexible Endoscope, Less Than 3.0 Cm43249 | 109 | $101 |
| New Patient Office Or Other Outpatient Visit With Moderate Level of Medical Decision Making, If Using Time, 45 Minutes Or More99204 | 106 | $153 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 21 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Omeprazole | 481 | 171 |
| Pantoprazole Sodium | 126 | 41 |
| Peg3350/Sod Sulf,bicarb,cl/Kclbrand: Gavilyte-G | 47 | 45 |
| Peg 3350/Sod Sulf,chlr/Pot/Magbrand: Suflave | 46 | 45 |
| Peg3350/Sod Sul/Nacl/Kcl/Asb/Cbrand: Plenvu | 38 | 38 |
| Sod Picosulf/Mag Ox/Citric Acbrand: Clenpiq | 38 | 37 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$199 across 9 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
Registry dates
- Enumerated
- 2005-09-19
- Last updated
- 2025-03-19
- Certified
- 2025-03-19
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.