Chang S. Joo, MD
NPI 1508868787ActiveIndividual· Internal Medicine, Nephrology· Modesto, CA
Internal Medicine, Nephrology (MD) with Modesto Kidney Medical Group, practicing in Modesto, California. Their prescriptions cost Medicare Part D more than their services did: $276,507 for 1,889 claims, against $170,605 paid for services in 2024. Astrazeneca Pharmaceuticals LP reported $17.00 in payments in 2025, mostly food and beverage. Lists Doctors Medical Center and 3 other hospitals as hospital affiliations.
Overview
| NPI | 1508868787 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Jun 1, 2005 |
| Last updated in NPPES | Feb 22, 2008 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Nephrology Primary | 207RN0300X | A481920 | 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 - Nephrology (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 436 |
|---|---|
| Services billed | 1,332 across 19 procedure codes |
| Paid by Medicare | $170,605 |
Part D prescriptions in 2024
| Prescriptions (claims) | 1,889 · 4,626 30-day fills |
|---|---|
| Patients | 364 |
| Total drug cost | $276,507 |
| Generic share | 83% of claims |
Education and affiliations
| Graduation year | 1980 |
|---|---|
| Medicare specialty | Nephrology |
| Secondary specialties | Internal Medicine |
Medical group
- Modesto Kidney Medical GroupModesto, CA · 5 clinicians
Hospital affiliations
- Doctors Medical CenterModesto, CA
- Emanuel Medical CenterTurlock, CA
- Memorial Medical CenterModesto, CA
- Oak Valley Hospital DistrictOakdale, CA
Other facilities
- Davita Archway Dialysis of ModestoDialysis facility · Modesto, CA
- Shc TurlockDialysis facility · Turlock, CA
- Usrc Modesto DialysisDialysis facility · Modesto, CA
- Usrc ParkwayDialysis facility · Modesto, CA
- Usrc Patterson DialysisDialysis facility · Patterson, CA
Industry payments (Open Payments)
- 2025$17.00 · 1 payment from 1 company
- 2024$44.75 · 2 payments from 2 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Astrazeneca Pharmaceuticals LP | $17.00 | 1 |
What the 2025 payments were for
- Food and Beverage$17.00 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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