NPPES file of Aug 9, 2026

Saundra Ngoc-Yen Nguyen

Internal Medicine Physician · San Francisco, CA

Saundra Ngoc-Yen Nguyen is an internal medicine physician with a practice address in San Francisco, California, and NPI 1902337850, issued on Mar 22, 2017. Check the license (California A158861, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1902337850
Name
Saundra Ngoc-Yen Nguyen
Primary taxonomy
Internal Medicine Physician 207R00000X
License number
A158861 CA
Self-reported in NPPES; status is on the state search
Practice location
505 Parnassus Ave RM M1480, San Francisco, CA 94143
Phone
(415) 476-1529
Enumerated
Mar 22, 2017
Record last updated
Mar 26, 2020 (not updated in 6 years: call before relying on the address or phone)
Medicare enrollment
Enrolled (PECOS I20210602001998); accepts Medicare assignment
Medical or professional school
University Of Texas Southwestern Medical School At Dallas, 2017
Telehealth
Offers telehealth (CMS)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Verify Saundra Ngoc-Yen Nguyen in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A158861
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

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36% fewer Medicare Part D claims than the average internal medicine physician in 2024

2,033 Medicare Part D claims for 317 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 18% of claims.

  1. Saundra Nguyen2,033
  2. Specialty average3,176

Most prescribed

  1. Atorvastatin Calcium127 claims
  2. Levothyroxine Sodium125 claims
  3. Ozempic116 claims
  4. Amlodipine Besylate88 claims
  5. Rosuvastatin Calcium87 claims
  6. Fluticasone Propionate69 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.

The MIPS final score for 2023 (Medicare payment program): 91.3 of 100

The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.

  1. Qualityout of 100 · 30% of the final score81.6
  2. Costnot scored (reweighted)
  3. Promoting interoperabilityout of 100 · 25%89.1
  4. Improvement activities40 of 40 points · 15%100.0

Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).

Bills Medicare through one group practice

  1. Baylor College OF MedicineHouston, TX

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Saundra Ngoc-Yen Nguyen among 17,696 internal medicine physician records in California

Saundra Ngoc-Yen Nguyen 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 2017, is newer than 81% of them.

  • NPI issued2017 · 81% of these records are older, 16% newer
  • In a Medicare fileYes · 79% of these records are
  • In the CMS Doctors and Clinicians fileYes · 63% of these records are
  • Graduated2017 · median 2004 among the 11,065 with a school on file
  • Record last updated2020 · 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.

The 8 internal medicine physician records with the nearest ZIP codes

  1. Nathan Bass, MDSan Francisco, CA 941431689638959
  2. Margaret Fang, MDSan Francisco, CA 941431417911462
  3. Katherine Julian, MDSan Francisco, CA 941431003879826
  4. John Kane, MDSan Francisco, CA 941431467416461
  5. Suneil Koliwad, M.D., PH.D.San Francisco, CA 941431225006687
  6. Bernard Lo, MDSan Francisco, CA 941431184688137
  7. Stephen McPhee, MDSan Francisco, CA 941431124082490
  8. Andrew Posselt, MDSan Francisco, CA 941431235193616

Common questions

What is Saundra Ngoc-Yen Nguyen's NPI number?

Saundra Ngoc-Yen Nguyen's National Provider Identifier (NPI) is 1902337850, issued on Mar 22, 2017. An NPI identifies a provider in billing; it is not a license.

Where is Saundra Ngoc-Yen Nguyen located?

The NPPES record lists a practice address at 505 Parnassus Ave RM M1480, San Francisco, CA, 94143. Phone: (415) 476-1529. Providers update this record themselves, so call before visiting.

How can I verify Saundra Ngoc-Yen Nguyen's license?

NPPES lists California license number A158861, 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 Saundra Ngoc-Yen Nguyen prescribe under Medicare Part D?

In 2024, Saundra Ngoc-Yen Nguyen had 2,033 Medicare Part D claims for 317 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.

What is Saundra Ngoc-Yen Nguyen's MIPS final score?

The 2023 MIPS final score is 91.3 of 100. The average among 454,083 clinicians with a measured score was 83.5.

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.