NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1649565755 M.D.
Verify on CMS → Nathaniel Piel, M.D.
Internal Medicine Physician in Knoxville, Tennessee.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,737 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
7K
Medicare Part D claims · 519 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
85%
generic claims · 14% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
95.7/100
▲ 12 pts above national avg 83.5 · Exceptional
Industry payments
$341.19
17 payments · CMS Open Payments (Sunshine Act)
Source: CMS Medicare Part D Prescriber Public Use File, 2023
What the federal data shows
Nathaniel Piel, M.D. reported a CMS MIPS final score of 95.7/100 - above the 83.5 national average - and filed 6,746 Medicare Part D claims in 2023.
- 95.7/100
- MIPS score · +12 vs avg
- 7K
- Part D claims, 2023
- 85%
- 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.
Nathaniel Piel, M.D.'s MIPS score vs every measured U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure. Clinicians whose score CMS assigned without scoring any category are excluded.
96 ≥ 78th percentile 78% of 454,083 measured providers are in lower value bands
Each bar is a band; taller bars hold more measured providers. 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 whole-score-point band: it counts only measured clinicians in lower score bands. A CMS MIPS metric is not a recommendation or a clinical-quality rating by PlainDoctor. See methodology § corpus placement.
Source CMS Merit-based Incentive Payment System (MIPS) · 2023
Where Nathaniel Piel, M.D. sits
This provider among internal medicine physician peers
Across the 34,612 internal medicine physician providers who report both Medicare Part D prescribing and a MIPS quality score, Nathaniel Piel, M.D. writes more Part D claims than 86% of them and scores higher on MIPS quality than 82% - placing this provider in the high-volume, high-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.
Part D claim volume vs MIPS quality, by specialty percentile
Each dot is one internal medicine physician peer from a representative sample of 60; the gold marker is Nathaniel Piel, M.D.. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
Nathaniel Piel, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting + 2 hospital affiliations - 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 Nathaniel Piel, M.D.?
High performer (top quartile)Primary specialty
Internal Medicine Physician
Medicare Part D claims
6,746 148% vs specialty avg
MIPS final score
95.7/100 12.2 pts vs avg
Specialty distribution in Tennessee
How Internal Medicine Physician compares to other specialties among Tennessee providers
Medicare quality performance, MIPS
Nathaniel Piel, M.D.'s 2023 MIPS final score plotted against the Internal Medicine Physician national average
- MIPS Final Score
- 95.7/100
- vs 83.5 national avg · 2023 performance year
MIPS final score (Internal Medicine Physician) - 95.7/100 vs national avg 83.5
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).
Nathaniel Piel, M.D. appears in the CMS NPPES registry as an Internal Medicine Physician provider holding M.D. credentials at 11440 PARKSIDE DR STE 302, Knoxville, TN, 37934, with a listed phone of (865) 218-9220. NPI 1649565755 was issued on 06/16/2011.
Medicare Part D records for calendar year 2023 show 6,746 prescription claims written by this provider, covering 519 Medicare beneficiaries and totaling roughly $848K in drug spend, split 14% brand-name and 85% generic by claim count, with an opioid prescribing rate of 0.6%. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 95.7/100 for the 2023 performance year (Quality 85.3), compared with the 83.5 average among clinicians with a measured score.
Internal Medicine Physician is a high-volume specialty nationwide, with 172,737 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
Provider Details
| NPI | 1649565755 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 06/16/2011 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
95.6914
Final Score
Measured-score avg: 83.5
85.2885
Quality
100
Promoting Interoperability
Reporting: Alternative Payment Model
Hospital and facility affiliations
Facilities where Nathaniel Piel, M.D. 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.
Faculty Internal Medicine PLLC
Knoxville, TN
Physiotherapy Associates Inc
Loudon, TN
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 Nathaniel Piel, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$341
Largest payer
Novo Nordisk 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.
Brand vs generic prescribing mix · Typical
Nathaniel Piel, M.D. - brand share 14.0%
Internal Medicine Physician average
14% brand-name claims vs 85% generic, on 6,746 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.
6,746
Total Claims
$848K
Total Drug Cost
519
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 15,899
- Total Day Supply
- 466,649
- Brand vs Generic
- 14% brand / 85% generic
- Brand Drug Cost
- $708K
- Generic Drug Cost
- $138K
- Opioid Claims
- 43 (0.6% rate)
- Antibiotic Claims
- 60
Patient Demographics
- Average Patient Age
- 74.9 years
- Avg HCC Risk Score
- 1.14
- Gender Split
- 38% female / 62% male
- Age Distribution
- <65: 27, 65-74: 210, 75-84: 232, 85+: 50
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Nathaniel Piel, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
495 claims
- Amlodipine Besylate
Amlodipine Besylate
348 claims
- Levothyroxine Sodium
Levothyroxine Sodium
251 claims
- Omeprazole
Omeprazole
226 claims
- Gabapentin
Gabapentin
225 claims
- Losartan Potassium
Losartan Potassium
201 claims
- Lisinopril 195
Lisinopril
195 claims
- Metformin Hcl 147
Metformin Hcl
147 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 495 |
| Amlodipine Besylate | 348 |
| Levothyroxine Sodium | 251 |
| Omeprazole | 226 |
| Gabapentin | 225 |
| Losartan Potassium | 201 |
| Lisinopril | 195 |
| Metformin Hcl | 147 |
| Pravastatin Sodium | 136 |
| Rosuvastatin Calcium | 121 |
* 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 Nathaniel Piel, M.D. fits within the Internal Medicine Physician landscape nationally.
172,737
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider
Nathaniel Piel, M.D.'s 6,746 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in Tennessee
Other clinicians with the same primary specialty enrolled in Tennessee, drawn from the same CMS NPPES roster as Piel.
Dr. Damon Abaray
MD
Nashville, TN
Dr. Samuel Abbas
MD
Hixson, TN
Dr. Matthew Abbate
MD
Nashville, TN
Dr. Kazeen Abdullah
M.D.
Smyrna, TN
Dr. Sarmed Abdullah
M.D.
Lexington, TN
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 Tennessee 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.
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Frequently Asked Questions
What is Nathaniel Piel, M.D.'s specialty? ▼
Nathaniel Piel, M.D. specializes in Internal Medicine Physician and practices in Knoxville, Tennessee. Credentials: M.D..
How much does Nathaniel Piel, M.D. prescribe under Medicare Part D? ▼
In 2023, Nathaniel Piel, M.D. wrote 6,746 Medicare Part D claims totaling $848K in drug costs for 519 beneficiaries.
What is Nathaniel Piel, M.D.'s Medicare quality score? ▼
Nathaniel Piel, M.D. has a CMS MIPS Final Score of 95.7/100 (Quality: 85.3). The average MIPS Final Score across the 454,083 clinicians with at least one published category score is 83.5; clinicians whose score CMS assigned without scoring any category are excluded from that average. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Nathaniel Piel, M.D. located? ▼
Nathaniel Piel, M.D. is located at 11440 PARKSIDE DR STE 302, Knoxville, TN, 37934. Phone: (865) 218-9220.
What is Nathaniel Piel, M.D.'s NPI number? ▼
Nathaniel Piel, M.D.'s National Provider Identifier (NPI) is 1649565755, issued on 06/16/2011.
Does Nathaniel Piel, M.D. prescribe more brand-name or generic drugs? ▼
Nathaniel Piel, M.D.'s prescribing is 14% brand-name and 85% generic drugs by claim count, with $708K in brand drug costs.
Does Nathaniel Piel, M.D. prescribe opioids? ▼
Yes, Nathaniel Piel, M.D. had 43 opioid claims in 2023 with an opioid prescribing rate of 0.6%.
How many Internal Medicine Physician providers are there in the US? ▼
There are 172,737 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 Nathaniel Piel, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Nathaniel Piel, M.D.'s most frequently prescribed drugs include Atorvastatin Calcium, Amlodipine Besylate, Levothyroxine Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Nathaniel Piel, M.D. accept Medicare? ▼
Nathaniel Piel, M.D. appears in CMS Medicare data with 6,746 Part D claims and 519 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Nathaniel Piel, M.D.'s credentials? ▼
Nathaniel Piel, M.D.'s NPI is 1649565755 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
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 (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
- Quality Performance
- CMS Merit-based Incentive Payment System (MIPS) - 2023 performance year.
- 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
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 May 2026.