2026 NPPES data Internal Medicine Physician NPI 1316444946
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Brian Mendoza

Internal Medicine Physician in Orange, California. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,858 in Internal Medicine Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration, see our methodology.

Federal data, no proprietary rating. We show these CMS records as-is - no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
67
Medicare Part D claims · 29 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
60%
generic claims · 40% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$167.71
2 payments · CMS Open Payments (Sunshine Act)
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Brian Mendoza filed 67 Medicare Part D claims in 2023 as a Internal Medicine Physician in Orange, California, prescribing 60% generic.

67
Part D claims, 2023
60%
generic prescribing
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.

Brian Mendoza's Medicare Part D volume vs every U.S. prescriber

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

67 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. 2K+: 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)

Brian Mendoza 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 Brian Mendoza?

Quality data not reported

NPI registry status

Active

Issued 04/10/2018

NPI 1316444946

Primary specialty

Internal Medicine Physician

High-volume

172,858 US NPIs in this specialty

Medicare Part D claims

67 98% 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
Behavior Technician - 17.3%Behavior Technician17.3%Marriage & Family Therapist - 5.5%Marriage & Family Therapist5.5%Student in an Organized Health Care Education/Training Program - 5%Student in an Organized Health Care Education/Training Program5%Mental Health Counselor - 3.9%Mental Health Counselor3.9%Pharmacist - 3.5%Pharmacist3.5%Clinical Social Worker - 3.1%Clinical Social Worker3.1%Internal Medicine Physician - 2.1%Internal Medicine Physician2.1%
Largest specialties in California (% of in-state providers)

Board certification

Not published by CMS

CMS does not publish a per-provider board-certification field in NPPES. PlainDoctor does not have a reliable per-specialty certification rate to show for Internal Medicine Physician. Verify directly:

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).

Brian Mendoza appears in the CMS NPPES registry as a Internal Medicine Physician provider at 101 THE CITY DR S, Orange, CA, 92868, with a listed phone of (714) 456-8888. NPI 1316444946 was issued on 04/10/2018. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Mendoza 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 67 prescription claims written by this provider, covering 29 Medicare beneficiaries and totaling roughly $79K in drug spend, split 40% brand-name and 60% generic by claim count. 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

101 THE CITY DR S
Orange, CA 92868

Provider Details

NPI 1316444946
Specialty Internal Medicine Physician
Gender Male
NPI Issued 04/10/2018

Hospital and facility affiliations

Facilities where Brian Mendoza 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.

UC Regents
Orange, 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 Brian Mendoza. Source: openpaymentsdata.cms.gov.

Total received

$168

Largest payer

Gilead Sciences, 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 Brian Mendoza. To verify Brian Mendoza'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.

Brand vs generic prescribing mix · Above average

Brian Mendoza - brand share 40.0%
Internal Medicine Physician average

40% brand-name claims vs 60% generic, on 67 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

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

67
Total Claims
$79K
Total Drug Cost
29
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
97
Total Day Supply
2,510
Brand vs Generic
40% brand / 60% generic
Brand Drug Cost
$76K
Generic Drug Cost
$3K

Patient Demographics

Average Patient Age
70.3 years
Avg HCC Risk Score
2.20
Gender Split
45% female / 55% 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
Vemlidy
Tenofovir Alafenamide
19

* 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 Brian Mendoza 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

Brian Mendoza's 67 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 Mendoza.

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

Before you book an appointment

Use this federal record as your verification checklist, not as a recommendation.

  • Confirm the NPI record is current in the official CMS registry, providers update their own NPPES details, and moves can lag. Verify this NPI
  • Check the active license and any disciplinary history with the California medical board, federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Internal Medicine Physician peer on Medicare volume and prescribing patterns. Compare providers

Medicare Part D and MIPS figures describe practice patterns in federal programs only, they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.

Frequently Asked Questions

What is Brian Mendoza's specialty?
Brian Mendoza specializes in Internal Medicine Physician and practices in Orange, California.
How much does Brian Mendoza prescribe under Medicare Part D?
In 2023, Brian Mendoza wrote 67 Medicare Part D claims totaling $79K in drug costs for 29 beneficiaries.
Where is Brian Mendoza located?
Brian Mendoza is located at 101 THE CITY DR S, Orange, CA, 92868. Phone: (714) 456-8888.
What is Brian Mendoza's NPI number?
Brian Mendoza's National Provider Identifier (NPI) is 1316444946, issued on 04/10/2018.
Does Brian Mendoza prescribe more brand-name or generic drugs?
Brian Mendoza's prescribing is 40% brand-name and 60% generic drugs by claim count, with $76K in brand drug costs.
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 Brian Mendoza prescribe most often?
Based on 2023 Medicare Part D data, Brian Mendoza's most frequently prescribed drugs include Vemlidy. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Brian Mendoza accept Medicare?
Brian Mendoza appears in CMS Medicare data with 67 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 Brian Mendoza's credentials?
Brian Mendoza's NPI is 1316444946. 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

Compiled from official public sources by the PlainDoctor editorial team.