Walter Gwang-Up Park, M.D.
NPI 1538355672ActiveIndividual· Internal Medicine, Gastroenterology· Stanford, CA
Internal Medicine, Gastroenterology (M.D.) in Stanford, California, trained at Johns Hopkins University School of Medicine (class of 2003). Their prescriptions cost Medicare Part D more than their services did: $307,441 for 273 claims, against $69,306 paid for services in 2024. Capsovision, Inc. was the largest of 10 companies reporting payments in 2025, $86,880 in all, mostly consulting fees.
Overview
| NPI | 1538355672 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Sep 21, 2007 |
| Last updated in NPPES | Aug 24, 2026 |
| Certified by provider | Aug 24, 2026 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Gastroenterology Primary | 207RG0100X | A88008 | 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 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 - Gastroenterology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 359 |
|---|---|
| Services billed | 540 across 24 procedure codes |
| Paid by Medicare | $69,306 |
Part D prescriptions in 2024
| Prescriptions (claims) | 273 · 412 30-day fills |
|---|---|
| Patients | 115 |
| Total drug cost | $307,441 |
| Generic share | 66% of claims |
Education and affiliations
| Medical school | Johns Hopkins University School of Medicine |
|---|---|
| Graduation year | 2003 |
| Medicare specialty | Gastroenterology |
| Secondary specialties | Internal Medicine |
| Telehealth | Offers telehealth |
Medical group
- Stanford Health CareStanford, CA · 3,122 clinicians
Hospital affiliations
- Stanford Health CareStanford, CA
- Stanford Health Care Tri-ValleyPleasanton, CA
Industry payments (Open Payments)
- 2025$86,880 · 23 payments from 10 companies
- 2024$66,463 · 13 payments from 5 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Capsovision, Inc. | $83,108 | 10 |
| Olympus America Inc. | $1,209 | 3 |
| Amgen Inc. | $1,166 | 3 |
| Aimmune Therapeutics, Inc. | $700.00 | 1 |
| Fujifilm Healthcare Americas Corporation | $179.01 | 1 |
What the 2025 payments were for
- Consulting Fee$85,608 · 14 payments
- Food and Beverage$762.91 · 7 payments
- Travel and Lodging$508.96 · 2 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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