William B. Ershler, M.D.
NPI 1669496881ActiveIndividual· Internal Medicine, Hematology & Oncology· Fairfax, VA
Internal Medicine, Hematology & Oncology (M.D.) in Fairfax, Virginia, trained at State University of Ny Upstate Medical University (class of 1974). Their prescriptions cost Medicare Part D more than their services did: $418,729 for 105 claims, against $18,891 paid for services in 2024. Pfizer Inc. was the largest of 2 companies reporting payments in 2025, $1,371 in all, mostly consulting fees.
Overview
| NPI | 1669496881 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | Yes |
| NPI issued | Jul 27, 2006 |
| Last updated in NPPES | Nov 27, 2023 |
| Certified by provider | Oct 16, 2020 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Hematology & Oncology Primary | 207RH0003X | 0101054727 | VA |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Nov 10, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 11, 2026 | No match | — |
| New York OMIG · Nov 11, 2026 | No match | — |
| Ohio Medicaid · Nov 11, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 11, 2026 | No match | — |
| Washington HCA · Nov 11, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Internal Medicine (DC); Practitioner - Internal Medicine (VA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 93 |
|---|---|
| Services billed | 203 across 7 procedure codes |
| Paid by Medicare | $18,891 |
Part D prescriptions in 2024
| Prescriptions (claims) | 105 · 163 30-day fills |
|---|---|
| Patients | 22 |
| Total drug cost | $418,729 |
| Generic share | 41% of claims |
Education and affiliations
| Medical school | State University of Ny Upstate Medical University |
|---|---|
| Graduation year | 1974 |
| Medicare specialty | Internal Medicine |
| Secondary specialties | Hematology/Oncology, Medical Oncology |
Medical group
- Inova Health Care ServicesAlexandria, VA · 1,817 clinicians
Hospital affiliation
- Inova Fairfax HospitalFalls Church, VA
Industry payments (Open Payments)
- 2025$1,371 · 3 payments from 2 companies
- 2024$20,908 · 16 payments from 1 company
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Pfizer Inc. | $1,257 | 2 |
| Terumo Bct, Inc. | $113.52 | 1 |
What the 2025 payments were for
- Consulting Fee$1,100 · 1 payment
- Travel and Lodging$157.05 · 1 payment
- Food and Beverage$113.52 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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