Theodore An Peng, MD
Internal Medicine Physician · San Francisco, CA
Theodore An Peng, MD is an internal medicine physician with a practice address in San Francisco, California, and NPI 1548722754, issued on Apr 5, 2019. Check the license (California A178392, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Theodore An Peng
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A178392 CA
Self-reported in NPPES; status is on the state search - Practice location
- 505 Parnassus Ave, San Francisco, CA 94143
- Phone
- (415) 476-1000
- Enumerated
- Apr 5, 2019
- Record last updated
- Aug 15, 2022
- Medicare enrollment
- Enrolled (PECOS I20220714002497); accepts Medicare assignment
- Medical or professional school
- University Of California, San Francisco School Of Medicine, 2019
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 505 Parnassus Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Sharon AbadaStudent in an Organized Health Care Education/Training Program1003492844
- Abul Abbas, MBBSAnatomic Pathology Physician1881652964
- Jesse Abelson, MDInternal Medicine Physician1083843817
- Rhonald AbitonaAcute Care Nurse Practitioner1164993473
Verify Theodore An Peng in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A178392Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
97% fewer Medicare Part D claims than the average internal medicine physician in 2024
104 Medicare Part D claims for 40 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Bills Medicare through one group practice
- Regents OF The University OF CaliforniaSan Francisco, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Theodore An Peng among 17,696 internal medicine physician records in California
Theodore An Peng, MD is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2019, is newer than 86% of them.
- NPI issued2019 · 86% of these records are older, 11% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2019 · median 2004 among the 11,065 with a school on file
- Record last updated2022 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
1,318 internal medicine physician records list a practice address in San Francisco
They are 1,318 of the 38,143 NPPES records with a practice address in San Francisco, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in San Francisco → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Nathan Bass, MDSan Francisco, CA 941431689638959
- Margaret Fang, MDSan Francisco, CA 941431417911462
- Katherine Julian, MDSan Francisco, CA 941431003879826
- John Kane, MDSan Francisco, CA 941431467416461
- Suneil Koliwad, M.D., PH.D.San Francisco, CA 941431225006687
- Bernard Lo, MDSan Francisco, CA 941431184688137
- Stephen McPhee, MDSan Francisco, CA 941431124082490
- Andrew Posselt, MDSan Francisco, CA 941431235193616
Common questions
What is Theodore An Peng, MD's NPI number?
Theodore An Peng, MD's National Provider Identifier (NPI) is 1548722754, issued on Apr 5, 2019. An NPI identifies a provider in billing; it is not a license.
Where is Theodore An Peng, MD located?
The NPPES record lists a practice address at 505 Parnassus Ave, San Francisco, CA, 94143. Phone: (415) 476-1000. Providers update this record themselves, so call before visiting.
How can I verify Theodore An Peng, MD's license?
NPPES lists California license number A178392, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Theodore An Peng, MD prescribe under Medicare Part D?
In 2024, Theodore An Peng, MD had 104 Medicare Part D claims for 40 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.