NPI registry status
Active
2026 NPPES data Infectious Disease Physician NPI 1144337213 MD
Verify on CMS → Gregory Anstead, MD
Infectious Disease 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 8,537 in Infectious Disease 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
1K
Medicare Part D claims · 41 beneficiaries · Infectious Disease Physician avg: 807
Generic prescribing
65%
generic claims · 35% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$16.2K
15 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2024
What the federal data shows
Gregory Anstead, MD filed 1,331 Medicare Part D claims in 2024 as an Infectious Disease Physician in San Antonio, Texas, prescribing 65% generic.
- 1K
- Part D claims, 2024
- 65%
- generic prescribing
- Likely
- board-certified (heuristic)
- ≥79th
- pct by Part D claim volume (lower-bound band)
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.
Federal trust snapshot
What official records show about Gregory Anstead, MD
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1144337213), first enumerated 08/24/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 1,331 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- Reported
Industry payment transparency
$16.2K in reported industry payments (15 transfers) in 2024 under the federal Sunshine Act — disclosed transfers of value, not a quality rating.
Source: CMS Open Payments
- State context
State board disciplinary context
Texas statewide board action statistics are published annually — these figures describe aggregate state activity, not Gregory Anstead, MD's individual license status. Verify directly with the state medical board.
Source: TMB annual report 2023
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1144337213 · Infectious Disease Physician
NPI-10 · ENUM-LEGACY · TAX-MID · RX-MID · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1144337213
- ENUM-LEGACY 2006
- TAX-MID 9K Infectious Disease
- RX-MID 1,331
- BOOK-LIGHT 544 in Texas
- PHOTO-ENUM Linden Hu · 2006
Gregory Anstead, MD's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2024, across all CMS prescribers nationally
1,331 ≥ 79th percentile 79% of 1,416,883 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2024
✓
Board certification likely (heuristic, not verified)
Gregory Anstead, 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).
What does the federal data show about Gregory Anstead, MD?
Quality data not reportedPrimary specialty
Infectious Disease Physician
Medicare Part D claims
1,331 65% vs specialty avg
Specialty distribution in Texas
How Infectious Disease Physician compares to other specialties among Texas 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 Infectious Disease Physician. Verify directly:
How MIPS and board certification work
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).
Practice Address
Provider Details
| NPI | 1144337213 |
|---|---|
| Specialty | Infectious Disease Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 08/24/2006 |
Hospital and facility affiliations
Facilities where Gregory Anstead, 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.
University OF Texas Health Science Center AT San Antonio
San Antonio, TX
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 Gregory Anstead, MD. Source: openpaymentsdata.cms.gov.
Total received
$16.2K
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 - 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 Gregory Anstead, MD. To verify Gregory Anstead, 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
Gregory Anstead, MD - brand share 35.0%
Infectious Disease Physician average
35% brand-name claims vs 65% generic, on 1,331 2024 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 2024.
1,331
Total Claims
$1.3M
Total Drug Cost
41
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 2,117.733
- Total Day Supply
- 62,140
- Brand vs Generic
- 35% brand / 65% generic
- Brand Drug Cost
- $1.3M
- Generic Drug Cost
- $28K
- Opioid Claims
- 168 (12.6% rate)
- Antibiotic Claims
- 19
Patient Demographics
- Average Patient Age
- 62.8 years
- Avg HCC Risk Score
- 1.84
- Age Distribution
- <65: 20, 65-74: 19, 75-84: N/A, 85+: N/A
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2024. Based on Medicare Part D data only.
What Gregory Anstead, MD prescribes most
Top Medicare Part D drugs by claim count, 2024
- Hydrocodone-Acetam…
Hydrocodone-Acetaminophen
137 claims
- Dovato
Dovato
129 claims
- Biktarvy
Biktarvy
70 claims
- Atorvastatin Calcium 49
Atorvastatin Calcium
49 claims
- Prezcobix 33
Prezcobix
33 claims
- Tamsulosin Hcl 33
Tamsulosin Hcl
33 claims
- Gabapentin 30
Gabapentin
30 claims
- Metformin Hcl Er 28
Metformin Hcl Er
28 claims
| Drug | Claims |
|---|---|
| Hydrocodone-Acetaminophen Hydrocodone/Acetaminophen | 137 |
| Dovato Dolutegravir Sodium/Lamivudine | 129 |
| Biktarvy Bictegrav/Emtricit/Tenofov Ala | 70 |
| Atorvastatin Calcium | 49 |
| Prezcobix Darunavir/Cobicistat | 33 |
| Tamsulosin Hcl | 33 |
| Gabapentin | 30 |
| Metformin Hcl Er Metformin Hcl | 28 |
| Pifeltro Doravirine | 27 |
| Descovy Emtricitabine/Tenofov Alafenam | 26 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Infectious Disease Physician Overview
How Gregory Anstead, MD fits within the Infectious Disease Physician landscape nationally.
8,537
Infectious Disease Physician Providers in US
54
States with Infectious Disease Physician
807
Avg Claims per Provider
Gregory Anstead, MD's 1,331 claims are above the specialty average of 807.
Nationwide Infectious Disease Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Anstead, both outside Texas so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Infectious Disease Physician Providers in Texas
Other clinicians with the same primary specialty enrolled in Texas, drawn from the same CMS NPPES roster as Anstead.
One of 544 Infectious Disease Physician providers enrolled in Texas, 5 are shown here.
Dr. Jordan Abel
M.D.
San Antonio, TX
Dr. Oladapo Abodunde
M.D.
McKinney, TX
Dr. Leny Abraham
MD
Dallas, TX
Dr. Ahmed Abubaker
MD
Dallas, TX
Dr. Ashish Acharya
M.D.
Grapevine, TX
Compare Infectious Disease Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Gregory Anstead, MD's specialty? ▼
Gregory Anstead, MD specializes in Infectious Disease Physician and practices in San Antonio, Texas. Credentials: MD.
How much does Gregory Anstead, MD prescribe under Medicare Part D? ▼
In 2024, Gregory Anstead, MD wrote 1,331 Medicare Part D claims totaling $1.3M in drug costs for 41 beneficiaries.
Where is Gregory Anstead, MD located? ▼
Gregory Anstead, MD is located at 4647 MEDICAL DR, San Antonio, TX, 78229. Phone: (210) 257-1400.
What is Gregory Anstead, MD's NPI number? ▼
Gregory Anstead, MD's National Provider Identifier (NPI) is 1144337213, issued on 08/24/2006.
Does Gregory Anstead, MD prescribe more brand-name or generic drugs? ▼
Gregory Anstead, MD's prescribing is 35% brand-name and 65% generic drugs by claim count, with $1.3M in brand drug costs.
Does Gregory Anstead, MD prescribe opioids? ▼
Yes, Gregory Anstead, MD had 168 opioid claims in 2024 with an opioid prescribing rate of 12.6%.
How many Infectious Disease Physician providers are there in the US? ▼
There are 8,537 Infectious Disease Physician providers across 54 states in the US. The average Infectious Disease Physician provider writes 807 Medicare Part D claims per year.
What drugs does Gregory Anstead, MD prescribe most often? ▼
Based on 2024 Medicare Part D data, Gregory Anstead, MD's most frequently prescribed drugs include Hydrocodone-Acetaminophen, Dovato, Biktarvy. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Gregory Anstead, MD accept Medicare? ▼
Gregory Anstead, MD appears in CMS Medicare data with 1,331 Part D claims and 41 Medicare beneficiaries in 2024. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Gregory Anstead, MD's credentials? ▼
Gregory Anstead, MD's NPI is 1144337213 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
View source datasets and methodology notes
- 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 (2024). 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 August 2026 (NPPES) / 2024 (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
Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of August 2026.