Matthew D. Armstrong, MD
NPI 1457363236ActiveIndividual· Internal Medicine, Hematology & Oncology· Tulsa, OK
Internal Medicine, Hematology & Oncology (MD) with Warren Clinic Inc and 1 other group, practicing in Tulsa, Oklahoma. Their prescriptions cost Medicare Part D more than their services did: $6,271,812 for 3,151 claims, against $100,489 paid for services in 2024. Pfizer Inc. was the largest of 7 companies reporting payments in 2025, $431.26 in all, mostly food and beverage. Lists Northeastern Health System and 4 other hospitals as hospital affiliations.
Overview
| NPI | 1457363236 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Aug 12, 2006 |
| Last updated in NPPES | Apr 13, 2021 |
| Certified by provider | Apr 13, 2021 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Hematology & Oncology Primary | 207RH0003X | 28451 | OK |
| Internal Medicine | 207R00000X | 48562 | MN |
| Internal Medicine | 207R00000X | ME101737 | FL |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 4, 2026 | No match | — |
| New York OMIG · Nov 4, 2026 | No match | — |
| Ohio Medicaid · Nov 4, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 4, 2026 | No match | — |
| Washington HCA · Nov 4, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Medical Oncology (OK) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 491 |
|---|---|
| Services billed | 2,504 across 14 procedure codes |
| Paid by Medicare | $100,489 |
Part D prescriptions in 2024
| Prescriptions (claims) | 3,151 · 4,510 30-day fills |
|---|---|
| Patients | 449 |
| Total drug cost | $6,271,812 |
| Generic share | 83% of claims |
Education and affiliations
| Graduation year | 2005 |
|---|---|
| Medicare specialty | Medical Oncology |
| Secondary specialties | Internal Medicine |
Medical groups
- Warren Clinic IncTulsa, OK · 883 clinicians
- Saint Francis Hospital, Inc.Tulsa, OK · 61 clinicians
Hospital affiliations
- Northeastern Health SystemTahlequah, OK
- Saint Francis Hospital MuskogeeMuskogee, OK
- Saint Francis Hospital South, LLCTulsa, OK
- Saint Francis Hospital Vinita, IncVinita, OK
- Saint Francis Hospital, IncTulsa, OK
Industry payments (Open Payments)
- 2025$431.26 · 29 payments from 7 companies
- 2024$312.91 · 17 payments from 5 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Pfizer Inc. | $151.63 | 14 |
| Abbvie Inc. | $97.53 | 5 |
| Novartis Pharmaceuticals Corporation | $75.37 | 4 |
| Ferring Pharmaceuticals Inc. | $35.09 | 2 |
| Gilead Sciences, Inc. | $34.66 | 2 |
What the 2025 payments were for
- Food and Beverage$279.63 · 15 payments
- Education$151.63 · 14 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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