Mark Chung-Hsun Tsai, M.D.
NPI 1225033111ActiveIndividual· Internal Medicine· Paramount, CA
Internal Medicine (M.D.) in Paramount, California, trained at University of Pittsburgh School of Medicine (class of 2001). Their prescriptions cost Medicare Part D more than their services did: $1,028,180 for 9,516 claims, against $55,733 paid for services in 2024. Madrigal Pharmaceuticals was the largest of 11 companies reporting payments in 2025, $2,095 in all, mostly food and beverage.
Overview
| NPI | 1225033111 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | Yes |
| NPI issued | Jun 16, 2005 |
| Last updated in NPPES | Apr 3, 2017 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | A81875 | 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 - Internal Medicine (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 211 |
|---|---|
| Services billed | 1,018 across 15 procedure codes |
| Paid by Medicare | $55,733 |
Part D prescriptions in 2024
| Prescriptions (claims) | 9,516 · 20,001 30-day fills |
|---|---|
| Patients | 472 |
| Total drug cost | $1,028,180 |
| Generic share | 85% of claims |
Education and affiliations
| Medical school | University of Pittsburgh School of Medicine |
|---|---|
| Graduation year | 2001 |
| Medicare specialty | Internal Medicine |
Hospital affiliations
- Memorialcare Long Beach Medical CenterLong Beach, CA
- Uci Health-OrangeOrange, CA
Other facilities
- Rae Star Health Systems, IncHome health agency · Cerritos, CA
Industry payments (Open Payments)
- 2025$2,095 · 69 payments from 11 companies
- 2024$1,842 · 69 payments from 16 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Madrigal Pharmaceuticals | $537.11 | 14 |
| Astrazeneca Pharmaceuticals LP | $367.35 | 17 |
| Amgen Inc. | $317.79 | 12 |
| Lilly USA, LLC | $200.31 | 8 |
| Gilead Sciences, Inc. | $191.74 | 6 |
What the 2025 payments were for
- Food and Beverage$2,095 · 69 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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