John J. Mazur, M.D.
NPI 1659364651ActiveIndividual· Internal Medicine, Pulmonary Disease· Great Falls, MT
Internal Medicine, Pulmonary Disease (M.D.) in Great Falls, Montana, trained at University of Michigan Medical School (class of 1986). Their prescriptions cost Medicare Part D more than their services did: $2,115,982 for 3,020 claims, against $218,979 paid for services in 2024. Intuitive Surgical, Inc. was the largest of 13 companies reporting payments in 2025, $9,052 in all, mostly education.
Overview
| NPI | 1659364651 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Aug 24, 2005 |
| Last updated in NPPES | Aug 10, 2011 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Pulmonary Disease Primary | 207RP1001X | 12032 | MT |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 10, 2026 | No match | — |
| New York OMIG · Nov 10, 2026 | No match | — |
| Ohio Medicaid · Nov 10, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 10, 2026 | No match | — |
| Washington HCA · Nov 10, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Pulmonary Disease (MT) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 372 |
|---|---|
| Services billed | 4,075 across 42 procedure codes |
| Paid by Medicare | $218,979 |
Part D prescriptions in 2024
| Prescriptions (claims) | 3,020 · 4,267 30-day fills |
|---|---|
| Patients | 360 |
| Total drug cost | $2,115,982 |
| Generic share | 45% of claims |
Education and affiliations
| Medical school | University of Michigan Medical School |
|---|---|
| Graduation year | 1986 |
| Medicare specialty | Pulmonary Disease |
| Secondary specialties | Critical Care (Intensivists) |
Medical group
- Great Falls Clinic LLCGreat Falls, MT · 72 clinicians
Hospital affiliations
- Benefis Hospitals IncGreat Falls, MT
- Great Falls Clinic HospitalGreat Falls, MT
- Northern Montana HospitalHavre, MT
Industry payments (Open Payments)
- 2025$9,052 · 47 payments from 13 companies
- 2024$1,159 · 47 payments from 15 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Intuitive Surgical, Inc. | $8,193 | 10 |
| Actelion Pharmaceuticals US, Inc. | $179.57 | 5 |
| Astrazeneca Pharmaceuticals LP | $174.33 | 8 |
| Glaxosmithkline, LLC. | $155.04 | 10 |
| Insmed, Inc. | $94.53 | 3 |
What the 2025 payments were for
- Education$7,100 · 5 payments
- Travel and Lodging$1,177 · 5 payments
- Food and Beverage$775.58 · 37 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
Other Internal Medicine, Pulmonary Disease providers in Great Falls
- 1083736227
- 1629450333
- 1871535096
- 1548261274
- 1386630952
- 1659395697
- 1306132279
- 1235342999
All Internal Medicine, Pulmonary Disease providers in Montana →