Darby Annette Clayson, MD
NPI 1619968021ActiveIndividual· Internal Medicine· San Francisco, CA
Internal Medicine (MD) in San Francisco, California, trained at Baylor College of Medicine (class of 1998). Their prescriptions cost Medicare Part D more than their services did: $287,609 for 3,474 claims, against $191,062 paid for services in 2024. Amgen Inc. reported $129.41 in payments in 2024, mostly food and beverage.
Overview
| NPI | 1619968021 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | Yes |
| NPI issued | Nov 3, 2005 |
| Last updated in NPPES | Feb 27, 2026 |
| Certified by provider | Feb 27, 2026 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | A139455 | CA |
| Military Health Care Provider | 171000000X | 11502 | NV |
| Internal Medicine | 207R00000X | 11502 | NV |
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 - Hospitalist (CA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 445 |
|---|---|
| Services billed | 1,971 across 16 procedure codes |
| Paid by Medicare | $191,062 |
Part D prescriptions in 2024
| Prescriptions (claims) | 3,474 · 3,591 30-day fills |
|---|---|
| Patients | 201 |
| Total drug cost | $287,609 |
| Generic share | 74% of claims |
Education and affiliations
| Medical school | Baylor College of Medicine |
|---|---|
| Graduation year | 1998 |
| Medicare specialty | Hospitalist |
| Secondary specialties | Internal Medicine |
Medical groups
- Vituity Hospitalists PCRedwood City, CA · 79 clinicians
- San Francisco Unified Physicians Group, IncSan Francisco, CA · 19 clinicians
Hospital affiliations
- Chinese HospitalSan Francisco, CA
- UCSF Health Saint Francis HospitalSan Francisco, CA
- UCSF Health St. Mary's HospitalSan Francisco, CA
Other facilities
- Lawton Skilled Nursing & Rehabilitation CenterNursing home · San Francisco, CA
Industry payments (Open Payments)
- 2024$129.41 · 1 payment from 1 company
Top paying companies in 2024
| Company | Amount | Payments |
|---|---|---|
| Amgen Inc. | $129.41 | 1 |
What the 2024 payments were for
- Food and Beverage$129.41 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
Other internal medicine physicians in San Francisco
- 1003871724
- 1003872870
- 1013000868
- 1013067040
- 1013080167
- 1013320738
- 1023016292
- 1023291945
- 1023332988
- 1023404860
- 1033140702
- 1043384050
All 1,457 internal medicine physicians in San Francisco · All internal medicine physicians in California