2026 NPPES data Gynecology Physician NPI 1487185583 M.D.
Verify on CMS →

JOSEPHINE NGUYEN, M.D.

Gynecology Physician in SANTA CLARA, California. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
49
Medicare Part D claims · 29 beneficiaries · Gynecology Physician avg: 295

What the federal data shows

JOSEPHINE NGUYEN, M.D. filed 49 Medicare Part D claims in 2023 as a Gynecology Physician in SANTA CLARA, California.

49
Part D claims, 2023
Likely
board-certified (heuristic)

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

JOSEPHINE NGUYEN, M.D.'s Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

49 0th percentile higher than 0% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). This entry sits in this band. 200–400: 182,923 prescribers (13%). Above this entry. 400–600: 90,619 prescribers (7%). Above this entry. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board certification likely (heuristic — not verified)

JOSEPHINE NGUYEN, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about JOSEPHINE NGUYEN, M.D.?

Quality data not reported

NPI registry status

Active

Issued 03/21/2017

NPI 1487185583

Primary specialty

Gynecology Physician

Niche

3,902 US NPIs in this specialty

Medicare Part D claims

49 83% vs specialty avg

2023 prescription claims

Specialty avg: 295

Specialty distribution in California

How Gynecology Physician compares to other specialties among California providers

California providers

Gynecology Physician share within California

1. Gynecology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Gynecology Physician share within California

Specialty board-certification context

Estimated specialty board-certified rate — Gynecology Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Gynecology Physician ABMS/AOA estimate

Est. board-certified rate (Gynecology Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Gynecology Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

JOSEPHINE NGUYEN, M.D. appears in the CMS NPPES registry as a Gynecology Physician provider holding M.D. credentials at 710 LAWRENCE EXPY DEPT 386, SANTA CLARA, CA, 95051, with a listed phone of (408) 851-1000. NPI 1487185583 was issued on 03/21/2017. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what NGUYEN most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 49 prescription claims written by this provider, covering 29 Medicare beneficiaries and totaling roughly $3K in drug spend. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Gynecology Physician is a narrow specialty nationwide, with 3,902 enrolled providers across 53 states and an average of 295 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

710 LAWRENCE EXPY DEPT 386
SANTA CLARA, CA 95051

Provider Details

NPI 1487185583
Specialty Gynecology Physician
Credentials M.D.
Gender Female
NPI Issued 03/21/2017

Hospital and facility affiliations

Facilities where JOSEPHINE NGUYEN, M.D. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

PERMANENTE MEDICAL GROUP INC
SANTA CLARA, CA

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

License & disciplinary context — California MBC 2023 annual report

Aggregate state board data only — NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~150K California medical licensees in 2023 — they are NOT specific to JOSEPHINE NGUYEN, M.D.. To verify JOSEPHINE NGUYEN, M.D.'s current license status, search the MBC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

576
Total board actions, California 2023
Across 556 cases
3.84
Actions per 1,000 licensees
California statewide rate
probation
Most common action type
186 cases

MBC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the California disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

49
Total Claims
$3K
Total Drug Cost
29
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
116
Total Day Supply
3,220
Generic Drug Cost
$1K

Patient Demographics

Average Patient Age
69.7 years
Avg HCC Risk Score
0.94
Gender Split
100% female / 0% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

Drug Claims
Estradiol
18

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Gynecology Physician Overview

How JOSEPHINE NGUYEN, M.D. fits within the Gynecology Physician landscape nationally.

3,902
Gynecology Physician Providers in US
53
States with Gynecology Physician
295
Avg Claims per Provider

JOSEPHINE NGUYEN, M.D.'s 49 claims are below the specialty average of 295.

Nearby Gynecology Physician Providers in California

Other clinicians with the same primary specialty enrolled in California, drawn from the same CMS NPPES roster as NGUYEN.

Compare Gynecology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is JOSEPHINE NGUYEN, M.D.'s specialty?
JOSEPHINE NGUYEN, M.D. specializes in Gynecology Physician and practices in SANTA CLARA, California. Credentials: M.D..
How much does JOSEPHINE NGUYEN, M.D. prescribe under Medicare Part D?
In 2023, JOSEPHINE NGUYEN, M.D. wrote 49 Medicare Part D claims totaling $3K in drug costs for 29 beneficiaries.
Where is JOSEPHINE NGUYEN, M.D. located?
JOSEPHINE NGUYEN, M.D. is located at 710 LAWRENCE EXPY DEPT 386, SANTA CLARA, CA, 95051. Phone: (408) 851-1000.
What is JOSEPHINE NGUYEN, M.D.'s NPI number?
JOSEPHINE NGUYEN, M.D.'s National Provider Identifier (NPI) is 1487185583, issued on 03/21/2017.
How many Gynecology Physician providers are there in the US?
There are 3,902 Gynecology Physician providers across 53 states in the US. The average Gynecology Physician provider writes 295 Medicare Part D claims per year.
What drugs does JOSEPHINE NGUYEN, M.D. prescribe most often?
Based on 2023 Medicare Part D data, JOSEPHINE NGUYEN, M.D.'s most frequently prescribed drugs include Estradiol. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does JOSEPHINE NGUYEN, M.D. accept Medicare?
JOSEPHINE NGUYEN, M.D. appears in CMS Medicare data with 49 Part D claims and 29 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify JOSEPHINE NGUYEN, M.D.'s credentials?
JOSEPHINE NGUYEN, M.D.'s NPI is 1487185583 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology