Tuan Xuan Nguyen, MD
NPI 1679519821ActiveIndividual· Internal Medicine· Garden Grove, CA
Internal Medicine (MD) in Garden Grove, California, trained at University of Oklahoma College of Medicine (class of 1989). Their prescriptions cost Medicare Part D more than their services did: $931,169 for 14,675 claims, against $419,202 paid for services in 2024. Phathom Pharmaceuticals, Inc. was the largest of 2 companies reporting payments in 2025, $155.92 in all, mostly food and beverage.
Overview
| NPI | 1679519821 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Jun 22, 2006 |
| Last updated in NPPES | Oct 15, 2018 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | A48636 | 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 - Internal Medicine (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 250 |
|---|---|
| Services billed | 7,840 across 27 procedure codes |
| Paid by Medicare | $419,202 |
Part D prescriptions in 2024
| Prescriptions (claims) | 14,675 · 24,119 30-day fills |
|---|---|
| Patients | 465 |
| Total drug cost | $931,169 |
| Generic share | 88% of claims |
Education and affiliations
| Medical school | University of Oklahoma College of Medicine |
|---|---|
| Graduation year | 1989 |
| Medicare specialty | Internal Medicine |
| Telehealth | Offers telehealth |
Industry payments (Open Payments)
- 2025$155.92 · 2 payments from 2 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Phathom Pharmaceuticals, Inc. | $124.26 | 1 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | $31.66 | 1 |
What the 2025 payments were for
- Food and Beverage$155.92 · 2 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All 67 internal medicine physicians in Garden Grove · All internal medicine physicians in California