Warren Choy, MD
NPI 1336227982 · Internal Medicine Physician · San Francisco, CA
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Warren Choy, MD is a Internal Medicine Physician provider in San Francisco, CA (NPI 1336227982).
Provider details
- NPI number
- 1336227982
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A55213 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 103 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Atorvastatin Calcium | 1,737 | 539 |
| Amlodipine Besylate | 752 | 236 |
| Losartan Potassium | 688 | 212 |
| Metformin Hclbrand: Metformin Hcl Er | 335 | 107 |
| Lisinopril | 313 | 98 |
| Metformin Hcl | 289 | 90 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-11-01
- Last updated
- 2021-12-03
Frequently asked questions
- What is Warren Choy's NPI number?
- Warren Choy's National Provider Identifier (NPI) is 1336227982, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Warren Choy's specialty?
- Warren Choy is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Warren Choy located?
- Warren Choy's practice location on file with NPPES is 2200 Ofarrell St, San Francisco, CA 94115-3357.
- What is Warren Choy's phone number?
- The practice phone number listed in the NPPES registry for Warren Choy is (415) 833-2000.
- Does Warren Choy accept Medicare?
- Warren Choy is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Warren Choy's NPI active?
- Yes — Warren Choy's NPI (1336227982) is active in the NPPES registry as of the last update on 2021-12-03.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.