May Y. Chiu, MD
NPI 1407857329ActiveIndividual· Internal Medicine, Nephrology· Walnut Creek, CA
Internal Medicine, Nephrology (MD) in Walnut Creek, California, trained at Albany Medical College of Union University (class of 1991). 476 Medicare patients in 2024, $302,188 paid; nearly all of their 857 Part D prescriptions were generic (91%). Fresenius USA Marketing, Inc. was the largest of 5 companies reporting payments in 2025, $501.22 in all, mostly food and beverage.
Overview
| NPI | 1407857329 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Aug 2, 2005 |
| Last updated in NPPES | Jul 8, 2007 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Nephrology Primary | 207RN0300X | G84473 | 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 | 476 |
|---|---|
| Services billed | 2,661 across 26 procedure codes |
| Paid by Medicare | $302,188 |
Part D prescriptions in 2024
| Prescriptions (claims) | 857 · 1,949 30-day fills |
|---|---|
| Patients | 164 |
| Total drug cost | $122,631 |
| Generic share | 91% of claims |
Education and affiliations
| Medical school | Albany Medical College of Union University |
|---|---|
| Graduation year | 1991 |
| Medicare specialty | Nephrology |
| Telehealth | Offers telehealth |
Medical group
- West Coast KidneyDaly City, CA · 56 clinicians
Hospital affiliations
- Contra Costa Regional Medical CenterMartinez, CA
- John Muir Medical Center - Concord CampusConcord, CA
- John Muir Medical Center - Walnut Creek CampusWalnut Creek, CA
- Sutter Delta Medical CenterAntioch, CA
Other facilities
- Fresenius Medical Care - Diablo BrentwoodDialysis facility · Brentwood, CA
- Fresenius Medical Care - Diablo Walnut CreekDialysis facility · Walnut Creek, CA
Industry payments (Open Payments)
- 2025$501.22 · 19 payments from 5 companies
- 2024$611.34 · 21 payments from 5 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Fresenius USA Marketing, Inc. | $229.26 | 14 |
| Apellis Pharmaceuticals, Inc. | $110.68 | 1 |
| Nxstage Medical, Inc. | $98.21 | 1 |
| Ardelyx, Inc. | $46.42 | 2 |
| Amgen Inc. | $16.65 | 1 |
What the 2025 payments were for
- Food and Beverage$501.22 · 19 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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