Steven R. Tolkan, MD
NPI 1871554766ActiveIndividual· Internal Medicine, Nephrology· Fairfield, CA
Internal Medicine, Nephrology (MD) in Fairfield, California, trained at University of Wisconsin School of Medicine (class of 1973). In 2024 Medicare paid $118,594 for 74 patients, and Part D covered 756 of their prescriptions, 88% of them generic. Amgen Inc. was the largest of 11 companies reporting payments in 2025, $476.06 in all, mostly food and beverage.
Overview
| NPI | 1871554766 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | Yes |
| NPI issued | Mar 30, 2006 |
| Last updated in NPPES | Apr 24, 2014 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Nephrology Primary | 207RN0300X | G83696 | CA |
| Internal Medicine | 207R00000X | G83696 | CA |
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 - Nephrology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 74 |
|---|---|
| Services billed | 687 across 12 procedure codes |
| Paid by Medicare | $118,594 |
Part D prescriptions in 2024
| Prescriptions (claims) | 756 · 1,109 30-day fills |
|---|---|
| Patients | 70 |
| Total drug cost | $107,908 |
| Generic share | 88% of claims |
Education and affiliations
| Medical school | University of Wisconsin School of Medicine |
|---|---|
| Graduation year | 1973 |
| Medicare specialty | Nephrology |
| Secondary specialties | Internal Medicine |
Hospital affiliations
- Northbay Medical CenterFairfield, CA
- Sutter Medical Center, SacramentoSacramento, CA
Other facilities
- Bma Santa RosaDialysis facility · Santa Rosa, CA
- Davita Fairfield Dialysis CenterDialysis facility · Fairfield, CA
- Davita Fairfield Downtown DialysisDialysis facility · Fairfield, CA
- Davita Vacaville Dialysis CenterDialysis facility · Vacaville, CA
Industry payments (Open Payments)
- 2025$476.06 · 17 payments from 11 companies
- 2024$385.98 · 14 payments from 7 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Amgen Inc. | $185.32 | 4 |
| Ardelyx, Inc. | $57.62 | 3 |
| Akebia Therapeutics Inc | $47.21 | 2 |
| Glaxosmithkline, LLC. | $30.00 | 1 |
| Mallinckrodt Hospital Products Inc. | $29.90 | 1 |
What the 2025 payments were for
- Food and Beverage$476.06 · 17 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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