William L. Peterson, M.D.
NPI 1174623854ActiveIndividual· Internal Medicine, Gastroenterology· Springfield, IL
Internal Medicine, Gastroenterology (M.D.) in Springfield, Illinois, trained at University of North Dakota School of Medicine (class of 1981). Their prescriptions cost Medicare Part D more than their services did: $2,198,544 for 4,457 claims, against $252,422 paid for services in 2024. Abbvie Inc. was the largest of 9 companies reporting payments in 2025, $2,333 in all, mostly food and beverage.
Overview
| NPI | 1174623854 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Sep 23, 2006 |
| Last updated in NPPES | May 21, 2020 |
| Certified by provider | May 21, 2020 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | 036-082538 | IL |
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 - Gastroenterology (IL) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 644 |
|---|---|
| Services billed | 8,479 across 61 procedure codes |
| Paid by Medicare | $252,422 |
Part D prescriptions in 2024
| Prescriptions (claims) | 4,457 · 8,658 30-day fills |
|---|---|
| Patients | 874 |
| Total drug cost | $2,198,544 |
| Generic share | 88% of claims |
Education and affiliations
| Medical school | University of North Dakota School of Medicine |
|---|---|
| Graduation year | 1981 |
| Medicare specialty | Gastroenterology |
| Secondary specialties | Internal Medicine |
Medical group
- Springfield Clinic, LLPSpringfield, IL · 687 clinicians
Hospital affiliations
- Abraham Lincoln Memorial HospitalLincoln, IL
- Decatur Memorial HospitalDecatur, IL
- Memorial Medical CenterSpringfield, IL
- St Johns HospitalSpringfield, IL
- Taylorville Memorial HospitalTaylorville, IL
Industry payments (Open Payments)
- 2025$2,333 · 65 payments from 9 companies
- 2024$1,439 · 49 payments from 8 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Abbvie Inc. | $590.19 | 28 |
| Madrigal Pharmaceuticals | $557.86 | 4 |
| Janssen Biotech, Inc. | $539.94 | 13 |
| Takeda Pharmaceuticals U.S.A., Inc. | $231.95 | 12 |
| Boston Scientific Corporation | $132.44 | 1 |
What the 2025 payments were for
- Food and Beverage$2,249 · 64 payments
- Education$84.00 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All 25 gastroenterologists in Springfield · All gastroenterologists in Illinois