NPI registry status
Active
2026 NPPES data Endocrinology, Diabetes & Metabolism Physician NPI 1598859480 M.D.
Verify on CMS → John Leahy, M.D.
Endocrinology, Diabetes & Metabolism Physician in Burlington, Vermont.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 7,852 in Endocrinology, Diabetes & Metabolism 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
98
Medicare Part D claims · 27 beneficiaries · Endocrinology, Diabetes & Metabolism Physician avg: 3K
Generic prescribing
0%
generic claims · 79% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
Compiled from official public sources by the PlainDoctor editorial team.
What the federal data shows
John Leahy, M.D. filed 98 Medicare Part D claims in 2023 as a Endocrinology, Diabetes & Metabolism Physician in Burlington, Vermont, prescribing 0% generic.
- 98
- Part D claims, 2023
- 0%
- 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.
John Leahy, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
98 0th percentile higher than 0% of 1,370,886 prescribers
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)
John Leahy, 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 John Leahy, M.D.?
Quality data not reportedPrimary specialty
Endocrinology, Diabetes & Metabolism Physician
Medicare Part D claims
98 96% vs specialty avg
Specialty distribution in Vermont
How Endocrinology, Diabetes & Metabolism Physician compares to other specialties among Vermont 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 Endocrinology, Diabetes & Metabolism 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).
John Leahy, M.D. appears in the CMS NPPES registry as a Endocrinology, Diabetes & Metabolism Physician provider holding M.D. credentials at 1 S PROSPECT ST, Burlington, VT, 05401, with a listed phone of (802) 847-4576. NPI 1598859480 was issued on 10/03/2006.
Medicare Part D records for calendar year 2023 show 98 prescription claims written by this provider, covering 27 Medicare beneficiaries and totaling roughly $101K in drug spend, split 79% brand-name and 0% generic by claim count.
Endocrinology, Diabetes & Metabolism Physician is a mid-sized specialty nationwide, with 7,852 enrolled providers across 54 states and an average of 2,639 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 | 1598859480 |
|---|---|
| Specialty | Endocrinology, Diabetes & Metabolism Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 10/03/2006 |
Brand vs generic prescribing mix · Brand-heavy
John Leahy, M.D. - brand share 79.0%
Endocrinology, Diabetes & Metabolism Physician average
79% brand-name claims vs 0% generic, on 98 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.
98
Total Claims
$101K
Total Drug Cost
27
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 224
- Total Day Supply
- 6,595
- Brand vs Generic
- 79% brand / 0% generic
- Brand Drug Cost
- $99K
Patient Demographics
- Average Patient Age
- 67.7 years
- Avg HCC Risk Score
- 1.67
- Gender Split
- 44% female / 56% 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 |
|---|---|
| Jardiance Empagliflozin | 16 |
| Ozempic Semaglutide | 14 |
| Lantus Solostar "Insulin Glargine | N/A |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Endocrinology, Diabetes & Metabolism Physician in VT →
All providers in Vermont →
Compare specialties →
Endocrinology, Diabetes & Metabolism Physician Overview
How John Leahy, M.D. fits within the Endocrinology, Diabetes & Metabolism Physician landscape nationally.
7,852
Endocrinology, Diabetes & Metabolism Physician Providers in US
54
States with Endocrinology, Diabetes & Metabolism Physician
2,639
Avg Claims per Provider
John Leahy, M.D.'s 98 claims are below the specialty average of 2,639.
Nearby Endocrinology, Diabetes & Metabolism Physician Providers in Vermont
Other clinicians with the same primary specialty enrolled in Vermont, drawn from the same CMS NPPES roster as Leahy.
Dr. Andrew Bauman
M.D.
White River Junction, VT
Dr. Rose Christian
MD
Burlington, VT
Dr. Margaret Daly
M.D.
Rutland, VT
Dr. David Felske
MD
Berlin, VT
Dr. Matthew Gilbert
DO, MPH
South Burlington, VT
Compare Endocrinology, Diabetes & Metabolism 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 Vermont medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Endocrinology, Diabetes & Metabolism 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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Medical Specialties Explained
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Understanding Medicare Claims Data
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Frequently Asked Questions
What is John Leahy, M.D.'s specialty? ▼
John Leahy, M.D. specializes in Endocrinology, Diabetes & Metabolism Physician and practices in Burlington, Vermont. Credentials: M.D..
How much does John Leahy, M.D. prescribe under Medicare Part D? ▼
In 2023, John Leahy, M.D. wrote 98 Medicare Part D claims totaling $101K in drug costs for 27 beneficiaries.
Where is John Leahy, M.D. located? ▼
John Leahy, M.D. is located at 1 S PROSPECT ST, Burlington, VT, 05401. Phone: (802) 847-4576.
What is John Leahy, M.D.'s NPI number? ▼
John Leahy, M.D.'s National Provider Identifier (NPI) is 1598859480, issued on 10/03/2006.
Does John Leahy, M.D. prescribe more brand-name or generic drugs? ▼
John Leahy, M.D.'s prescribing is 79% brand-name and 0% generic drugs by claim count, with $99K in brand drug costs.
How many Endocrinology, Diabetes & Metabolism Physician providers are there in the US? ▼
There are 7,852 Endocrinology, Diabetes & Metabolism Physician providers across 54 states in the US. The average Endocrinology, Diabetes & Metabolism Physician provider writes 2,639 Medicare Part D claims per year.
What drugs does John Leahy, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, John Leahy, M.D.'s most frequently prescribed drugs include Jardiance, Ozempic, Lantus Solostar. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John Leahy, M.D. accept Medicare? ▼
John Leahy, M.D. appears in CMS Medicare data with 98 Part D claims and 27 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John Leahy, M.D.'s credentials? ▼
John Leahy, M.D.'s NPI is 1598859480 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.
- 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.