Mark K. Yamanaka, M.D.
NPI 1013004852ActiveIndividual· Internal Medicine, Pulmonary Disease· Oceanside, CA
Internal Medicine, Pulmonary Disease (M.D.) in Oceanside, California, trained at University of California, Davis School of Medicine (class of 1981). Their prescriptions cost Medicare Part D more than their services did: $135,864 for 429 claims, against $82,330 paid for services in 2024. Glaxosmithkline, LLC. was the largest of 20 companies reporting payments in 2025, $1,629 in all, mostly food and beverage.
Overview
| NPI | 1013004852 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | Yes |
| NPI issued | Oct 5, 2006 |
| Last updated in NPPES | Jul 12, 2023 |
| Certified by provider | Jul 12, 2023 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Pulmonary Disease Primary | 207RP1001X | G48542 | CA |
| Internal Medicine, Critical Care Medicine | 207RC0200X | G48542 | CA |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 4, 2026 | No match | — |
| New York OMIG · Nov 4, 2026 | No match | — |
| Ohio Medicaid · Nov 4, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 4, 2026 | No match | — |
| Washington HCA · Nov 4, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Pulmonary Disease (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 247 |
|---|---|
| Services billed | 874 across 22 procedure codes |
| Paid by Medicare | $82,330 |
Part D prescriptions in 2024
| Prescriptions (claims) | 429 · 597 30-day fills |
|---|---|
| Patients | 104 |
| Total drug cost | $135,864 |
| Generic share | 61% of claims |
Education and affiliations
| Medical school | University of California, Davis School of Medicine |
|---|---|
| Graduation year | 1981 |
| Medicare specialty | Pulmonary Disease |
| Secondary specialties | Critical Care (Intensivists) |
Medical groups
- Cep America - Intensivists PCSanta Rosa, CA · 125 clinicians
- Pulmonary Specialists of North County IncOceanside, CA · 4 clinicians
Hospital affiliation
- Tri-City Medical CenterOceanside, CA
Industry payments (Open Payments)
- 2025$1,629 · 77 payments from 20 companies
- 2024$1,260 · 61 payments from 12 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Glaxosmithkline, LLC. | $354.12 | 19 |
| Actelion Pharmaceuticals US, Inc. | $163.76 | 6 |
| Viatris Specialty LLC | $163.27 | 14 |
| Regeneron Healthcare Solutions, Inc. | $127.85 | 5 |
| Abiomed | $120.26 | 1 |
What the 2025 payments were for
- Food and Beverage$1,629 · 77 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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