2026 NPPES data Obstetrics & Gynecology Physician NPI 1023125010 MD
Verify on CMS →

Karen Diaz, MD

Obstetrics & Gynecology Physician in San Antonio, Texas. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 44,313 in Obstetrics & Gynecology 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
50
Medicare Part D claims · 23 beneficiaries · Obstetrics & Gynecology Physician avg: 179
Generic prescribing
60%
generic claims · 40% brand-name · higher generic rates reduce patient out-of-pocket costs
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Karen Diaz, MD filed 50 Medicare Part D claims in 2023 as a Obstetrics & Gynecology Physician in San Antonio, Texas, prescribing 60% generic.

50
Part D claims, 2023
60%
generic prescribing

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.

Karen Diaz, MD's Medicare Part D volume vs every U.S. prescriber

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

50 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-eligible specialty (heuristic, not verified)

Karen Diaz, MD practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about Karen Diaz, MD?

Quality data not reported

NPI registry status

Active

Issued 08/24/2006

NPI 1023125010

Primary specialty

Obstetrics & Gynecology Physician

Mid-sized

44,313 US NPIs in this specialty

Medicare Part D claims

50 72% vs specialty avg

2023 prescription claims

Specialty avg: 179

Specialty distribution in Texas

How Obstetrics & Gynecology Physician compares to other specialties among Texas providers

Texas providers
Behavior Technician - 5.6%Behavior Technician5.6%Student in an Organized Health Care Education/Training Program - 5.1%Student in an Organized Health Care Education/Training Program5.1%Family Nurse Practitioner - 4.5%Family Nurse Practitioner4.5%Professional Counselor - 4.4%Professional Counselor4.4%Pharmacist - 4.4%Pharmacist4.4%Speech-Language Pathologist - 3.9%Speech-Language Pathologist3.9%Obstetrics & Gynecology Physician - 0.8%Obstetrics & Gynecology Physician0.8%
Largest specialties in Texas (% 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 Obstetrics & Gynecology 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).

Karen Diaz, MD appears in the CMS NPPES registry as a Obstetrics & Gynecology Physician provider holding MD credentials at 8300 FLOYD CURL DR FL 5, San Antonio, TX, 78229, with a listed phone of (210) 450-9500. NPI 1023125010 was issued on 08/24/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Diaz 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 50 prescription claims written by this provider, covering 23 Medicare beneficiaries and totaling roughly $15K 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.

Obstetrics & Gynecology Physician is a mid-sized specialty nationwide, with 44,313 enrolled providers across 56 states and an average of 179 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

8300 FLOYD CURL DR FL 5
San Antonio, TX 78229

Provider Details

NPI 1023125010
Specialty Obstetrics & Gynecology Physician
Credentials MD
Gender Female
NPI Issued 08/24/2006

License & disciplinary context - Texas TMB 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 ~77K Texas medical licensees in 2023 - they are NOT specific to Karen Diaz, MD. To verify Karen Diaz, MD's current license status, search the TMB public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

344
Total board actions, Texas 2023
Across 334 cases
4.47
Actions per 1,000 licensees
Texas statewide rate
probation
Most common action type
94 cases

TMB 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 Texas disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Above average

Karen Diaz, MD - brand share 40.0%
Obstetrics & Gynecology Physician average

40% brand-name claims vs 60% generic, on 50 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.

50
Total Claims
$15K
Total Drug Cost
23
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
93
Total Day Supply
2,654
Brand vs Generic
40% brand / 60% generic
Brand Drug Cost
$12K
Generic Drug Cost
$3K

Patient Demographics

Average Patient Age
71.6 years
Avg HCC Risk Score
1.21
Gender Split
100% female / 0% male

Obstetrics & Gynecology Physician Overview

How Karen Diaz, MD fits within the Obstetrics & Gynecology Physician landscape nationally.

44,313
Obstetrics & Gynecology Physician Providers in US
56
States with Obstetrics & Gynecology Physician
179
Avg Claims per Provider

Karen Diaz, MD's 50 claims are below the specialty average of 179.

Nearby Obstetrics & Gynecology Physician Providers in Texas

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

Compare Obstetrics & Gynecology 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 Texas medical board, federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Obstetrics & Gynecology 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 Karen Diaz, MD's specialty?
Karen Diaz, MD specializes in Obstetrics & Gynecology Physician and practices in San Antonio, Texas. Credentials: MD.
How much does Karen Diaz, MD prescribe under Medicare Part D?
In 2023, Karen Diaz, MD wrote 50 Medicare Part D claims totaling $15K in drug costs for 23 beneficiaries.
Where is Karen Diaz, MD located?
Karen Diaz, MD is located at 8300 FLOYD CURL DR FL 5, San Antonio, TX, 78229. Phone: (210) 450-9500.
What is Karen Diaz, MD's NPI number?
Karen Diaz, MD's National Provider Identifier (NPI) is 1023125010, issued on 08/24/2006.
Does Karen Diaz, MD prescribe more brand-name or generic drugs?
Karen Diaz, MD's prescribing is 40% brand-name and 60% generic drugs by claim count, with $12K in brand drug costs.
How many Obstetrics & Gynecology Physician providers are there in the US?
There are 44,313 Obstetrics & Gynecology Physician providers across 56 states in the US. The average Obstetrics & Gynecology Physician provider writes 179 Medicare Part D claims per year.
Does Karen Diaz, MD accept Medicare?
Karen Diaz, MD appears in CMS Medicare data with 50 Part D claims and 23 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Karen Diaz, MD's credentials?
Karen Diaz, MD's NPI is 1023125010 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

Compiled from official public sources by the PlainDoctor editorial team.