2026 NPPES data Internal Medicine Physician NPI 1023639804 MD
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PAUL AGUILERA, MD

Internal Medicine Physician in FREMONT, 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
182
Medicare Part D claims · 56 beneficiaries · Internal Medicine Physician avg: 3K
Industry payments
$60.37
2 payments · CMS Open Payments (Sunshine Act)
What the federal data reveals: PAUL AGUILERA, MD is a Internal Medicine Physician ([object Object]) practicing in FREMONT, California with a Medicare Part D prescribing footprint of 182 claims across 56 beneficiaries . Industry payments of $60.37 across 2 transactions are disclosed under CMS Open Payments (Sunshine Act).

What stands out: PAUL AGUILERA, MD filed 182 Medicare Part D claims in 2023 across FREMONT, California. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

PAUL AGUILERA, MD 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).

PAUL AGUILERA, MD at a glance

Quality data not reported

NPI registry status

Active

Issued 05/02/2020

NPI 1023639804

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

182 93% vs specialty avg

2023 prescription claims

Specialty avg: 2,716

Specialty distribution in California

How Internal Medicine Physician compares to other specialties among California providers

California providers

Internal Medicine Physician share within California

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

Specialty board-certification context

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

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

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

0%100%78%
Est. board-certified rate (Internal Medicine 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).

PAUL AGUILERA, MD is a Internal Medicine Physician provider practicing in FREMONT, California, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: MD. NPI: 1023639804. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

PAUL AGUILERA, MD appears in the CMS NPPES registry as a Internal Medicine Physician provider holding MD credentials at 2000 MOWRY AVE, FREMONT, CA, 94538, with a listed phone of (510) 797-1111. NPI 1023639804 was issued on 05/02/2020. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what AGUILERA 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 182 prescription claims written by this provider, covering 56 Medicare beneficiaries and totaling roughly $16K 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.

Internal Medicine Physician is a high-volume specialty nationwide, with 172,858 enrolled providers across 56 states and an average of 2,716 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

2000 MOWRY AVE
FREMONT, CA 94538

Provider Details

NPI 1023639804
Specialty Internal Medicine Physician
Credentials MD
Gender Male
NPI Issued 05/02/2020

Hospital and facility affiliations

Facilities where PAUL AGUILERA, MD 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.

HOSPITALIST MEDICINE PHYSICIANS OF CALIFORNIA INC
FREMONT, 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).

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for PAUL AGUILERA, MD. Source: openpaymentsdata.cms.gov.

Total received

$60

Largest payer

PFIZER INC.

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

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 PAUL AGUILERA, MD. To verify PAUL AGUILERA, MD'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.

182
Total Claims
$16K
Total Drug Cost
56
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
262
Total Day Supply
6,530
Generic Drug Cost
$3K
Antibiotic Claims
32

Patient Demographics

Average Patient Age
72.3 years
Avg HCC Risk Score
2.67
Gender Split
50% female / 50% 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
Olmesartan-Hydrochlorothiazide
Olmesartan/Hydrochlorothiazide
11

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

Internal Medicine Physician Overview

How PAUL AGUILERA, MD fits within the Internal Medicine Physician landscape nationally.

172,858
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider

PAUL AGUILERA, MD's 182 claims are below the specialty average of 2,716.

Nearby Internal Medicine Physician Providers in California

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

Compare Internal Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is PAUL AGUILERA, MD's specialty?
PAUL AGUILERA, MD specializes in Internal Medicine Physician and practices in FREMONT, California. Credentials: MD.
How much does PAUL AGUILERA, MD prescribe under Medicare Part D?
In 2023, PAUL AGUILERA, MD wrote 182 Medicare Part D claims totaling $16K in drug costs for 56 beneficiaries.
Where is PAUL AGUILERA, MD located?
PAUL AGUILERA, MD is located at 2000 MOWRY AVE, FREMONT, CA, 94538. Phone: (510) 797-1111.
What is PAUL AGUILERA, MD's NPI number?
PAUL AGUILERA, MD's National Provider Identifier (NPI) is 1023639804, issued on 05/02/2020.
How many Internal Medicine Physician providers are there in the US?
There are 172,858 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,716 Medicare Part D claims per year.
What drugs does PAUL AGUILERA, MD prescribe most often?
Based on 2023 Medicare Part D data, PAUL AGUILERA, MD's most frequently prescribed drugs include Olmesartan-Hydrochlorothiazide. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does PAUL AGUILERA, MD accept Medicare?
PAUL AGUILERA, MD appears in CMS Medicare data with 182 Part D claims and 56 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify PAUL AGUILERA, MD's credentials?
PAUL AGUILERA, MD's NPI is 1023639804 with credentials MD. 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