2026 NPPES data Sleep Medicine (Internal Medicine) Physician NPI 1013006063 M.D.
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NANCY ESPER, M.D.

Sleep Medicine (Internal Medicine) Physician in BELLAIRE, Texas. 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
2K
Medicare Part D claims · 141 beneficiaries · Sleep Medicine (Internal Medicine) Physician avg: 1K
Generic prescribing
84%
generic claims · 16% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$1.6K
63 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

NANCY ESPER, M.D. filed 2,029 Medicare Part D claims in 2023 as a Sleep Medicine (Internal Medicine) Physician in BELLAIRE, Texas, prescribing 84% generic.

2K
Part D claims, 2023
84%
generic prescribing
$1.6K
industry payments (Sunshine Act)

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.

NANCY ESPER, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

2,029 Top 16% higher than 84% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. 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)

NANCY ESPER, M.D. 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 NANCY ESPER, M.D.?

Quality data not reported

NPI registry status

Active

Issued 10/11/2006

NPI 1013006063

Primary specialty

Sleep Medicine (Internal Medicine) Physician

Niche

857 US NPIs in this specialty

Medicare Part D claims

2,029 55% vs specialty avg

2023 prescription claims

Specialty avg: 1,310

Specialty distribution in Texas

How Sleep Medicine (Internal Medicine) Physician compares to other specialties among Texas providers

Texas providers

Sleep Medicine (Internal Medicine) Physician share within Texas

1. Sleep Medicine (Internal Medicine) Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Sleep Medicine (Internal Medicine) Physician share within Texas

Specialty board-certification context

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

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

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

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

NANCY ESPER, M.D. appears in the CMS NPPES registry as a Sleep Medicine (Internal Medicine) Physician provider holding M.D. credentials at 5959 WEST LOOP S STE 510, BELLAIRE, TX, 77401, with a listed phone of (713) 429-4097. NPI 1013006063 was issued on 10/11/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what ESPER 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 2,029 prescription claims written by this provider, covering 141 Medicare beneficiaries and totaling roughly $274K in drug spend, split 16% brand-name and 84% generic by claim count, with an opioid prescribing rate of 1.4%. 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.

Sleep Medicine (Internal Medicine) Physician is a narrow specialty nationwide, with 857 enrolled providers across 52 states and an average of 1,310 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

5959 WEST LOOP S STE 510
BELLAIRE, TX 77401

Provider Details

NPI 1013006063
Specialty Sleep Medicine (Internal Medicine) Physician
Credentials M.D.
Gender Female
NPI Issued 10/11/2006

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 NANCY ESPER, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$1.6K

Largest payer

Amgen 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 NANCY ESPER, M.D.. To verify NANCY ESPER, M.D.'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 · Typical

NANCY ESPER, M.D. — brand share 16.0%
Specialty average (est.)

16% brand-name claims vs 84% generic, on 2,029 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.

2,029
Total Claims
$274K
Total Drug Cost
141
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
4,498
Total Day Supply
128,132
Brand vs Generic
16% brand / 84% generic
Brand Drug Cost
$230K
Generic Drug Cost
$44K
Opioid Claims
28 (1.4% rate)
Antibiotic Claims
90

Patient Demographics

Average Patient Age
73.8 years
Avg HCC Risk Score
0.98
Gender Split
80% female / 20% male

Top Prescribed Drugs (Medicare Part D)

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

What NANCY ESPER, M.D. prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Atorvastatin Calcium
100
Rosuvastatin Calcium
100
Levothyroxine Sodium
83
Metoprolol Succinate
68
Amlodipine Besylate
58
Hydrochlorothiazide
58
Olmesartan Medoxomil
57
Lisinopril
51
Ozempic
Semaglutide
45
Synthroid
Levothyroxine Sodium
42

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

Sleep Medicine (Internal Medicine) Physician Overview

How NANCY ESPER, M.D. fits within the Sleep Medicine (Internal Medicine) Physician landscape nationally.

857
Sleep Medicine (Internal Medicine) Physician Providers in US
52
States with Sleep Medicine (Internal Medicine) Physician
1,310
Avg Claims per Provider

NANCY ESPER, M.D.'s 2,029 claims are above the specialty average of 1,310.

Nearby Sleep Medicine (Internal Medicine) Physician Providers in Texas

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

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

Frequently Asked Questions

What is NANCY ESPER, M.D.'s specialty?
NANCY ESPER, M.D. specializes in Sleep Medicine (Internal Medicine) Physician and practices in BELLAIRE, Texas. Credentials: M.D..
How much does NANCY ESPER, M.D. prescribe under Medicare Part D?
In 2023, NANCY ESPER, M.D. wrote 2,029 Medicare Part D claims totaling $274K in drug costs for 141 beneficiaries.
Where is NANCY ESPER, M.D. located?
NANCY ESPER, M.D. is located at 5959 WEST LOOP S STE 510, BELLAIRE, TX, 77401. Phone: (713) 429-4097.
What is NANCY ESPER, M.D.'s NPI number?
NANCY ESPER, M.D.'s National Provider Identifier (NPI) is 1013006063, issued on 10/11/2006.
Does NANCY ESPER, M.D. prescribe more brand-name or generic drugs?
NANCY ESPER, M.D.'s prescribing is 16% brand-name and 84% generic drugs by claim count, with $230K in brand drug costs.
Does NANCY ESPER, M.D. prescribe opioids?
Yes, NANCY ESPER, M.D. had 28 opioid claims in 2023 with an opioid prescribing rate of 1.4%.
How many Sleep Medicine (Internal Medicine) Physician providers are there in the US?
There are 857 Sleep Medicine (Internal Medicine) Physician providers across 52 states in the US. The average Sleep Medicine (Internal Medicine) Physician provider writes 1,310 Medicare Part D claims per year.
What drugs does NANCY ESPER, M.D. prescribe most often?
Based on 2023 Medicare Part D data, NANCY ESPER, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Rosuvastatin Calcium, Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does NANCY ESPER, M.D. accept Medicare?
NANCY ESPER, M.D. appears in CMS Medicare data with 2,029 Part D claims and 141 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify NANCY ESPER, M.D.'s credentials?
NANCY ESPER, M.D.'s NPI is 1013006063 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