Farshid Dayyani, M.D., PH.D.
NPI 1376710434ActiveIndividual· Internal Medicine, Medical Oncology· Orange, CA
Internal Medicine, Medical Oncology (M.D., PH.D.) with Uc Regents, practicing in Orange, California. Their prescriptions cost Medicare Part D more than their services did: $664,964 for 604 claims, against $62,737 paid for services in 2024. Takeda Pharmaceuticals U.S.A., Inc. was the largest of 12 companies reporting payments in 2025, $289,318 in all, mostly speaking and faculty fees. Lists Uci Health-Orange as a hospital affiliation.
Overview
| NPI | 1376710434 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D., PH.D. |
| Sole proprietor | Yes |
| NPI issued | May 8, 2008 |
| Last updated in NPPES | Oct 20, 2022 |
| Certified by provider | Oct 20, 2022 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Medical Oncology Primary | 207RX0202X | A125971 | CA |
| General Acute Care Hospital | 282N00000X | 228902 | MA |
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 | 182 |
|---|---|
| Services billed | 779 across 10 procedure codes |
| Paid by Medicare | $62,737 |
Part D prescriptions in 2024
| Prescriptions (claims) | 604 · 750 30-day fills |
|---|---|
| Patients | 88 |
| Total drug cost | $664,964 |
| Generic share | 83% of claims |
Education and affiliations
| Graduation year | 2002 |
|---|---|
| Medicare specialty | Internal Medicine |
| Secondary specialties | Medical Oncology |
| Telehealth | Offers telehealth |
Medical group
- Uc RegentsOrange, CA · 319 clinicians
Hospital affiliation
- Uci Health-OrangeOrange, CA
Industry payments (Open Payments)
- 2025$289,318 · 165 payments from 12 companies
- 2024$266,863 · 159 payments from 11 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Takeda Pharmaceuticals U.S.A., Inc. | $98,408 | 47 |
| Astellas Pharma US Inc | $77,691 | 46 |
| Sirtex Medical Inc | $47,217 | 32 |
| Beone Medicines USA, Inc. | $39,966 | 23 |
| Ipsen Biopharmaceuticals, Inc | $10,182 | 5 |
What the 2025 payments were for
- Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program$235,493 · 49 payments
- Travel and Lodging$32,986 · 68 payments
- Consulting Fee$16,729 · 7 payments
- Food and Beverage$4,110 · 41 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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