Ryan D. Holzmacher, MD
NPI 1598700601ActiveIndividual· Internal Medicine· Greenfield, WI
Internal Medicine (MD) in Greenfield, Wisconsin, trained at Southern Illinois University School of Medicine (class of 1999). In 2024 Medicare paid $291,563 for 858 patients, and Part D covered 67 of their prescriptions, 64% of them generic.
Overview
| NPI | 1598700601 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Jun 20, 2006 |
| Last updated in NPPES | Sep 20, 2024 |
| Certified by provider | Sep 20, 2024 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | 42642-020 | WI |
| Internal Medicine, Nephrology | 207RN0300X | 42642-020 | WI |
| Pain Medicine, Pain Medicine | 208VP0000X | 42642-020 | WI |
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 (WI) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 858 |
|---|---|
| Services billed | 4,134 across 10 procedure codes |
| Paid by Medicare | $291,563 |
Part D prescriptions in 2024
| Prescriptions (claims) | 67 · 67 30-day fills |
|---|---|
| Patients | 25 |
| Total drug cost | $5,996 |
| Generic share | 64% of claims |
Education and affiliations
| Medical school | Southern Illinois University School of Medicine |
|---|---|
| Graduation year | 1999 |
| Medicare specialty | Internal Medicine |
| Secondary specialties | Nephrology |
Medical group
- Oak Medical SCLodi, WI · 123 clinicians
Hospital affiliation
- Waukesha Memorial HospitalWaukesha, WI
Other facilities
- Rehabilitation Hospital of WisconsinInpatient rehabilitation facility · Waukesha, WI
Industry payments (Open Payments)
None reported for 2025 or 2024.
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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