2026 NPPES data Gastroenterology Physician NPI 1487747242 M.D.
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John Horwhat, M.D.

Gastroenterology Physician in Lancaster, Pennsylvania.

This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 16,601 in Gastroenterology 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
251
Medicare Part D claims · 102 beneficiaries · Gastroenterology Physician avg: 833
Generic prescribing
82%
generic claims · 18% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$1.1K
31 payments · CMS Open Payments (Sunshine Act)
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

John Horwhat, M.D. filed 251 Medicare Part D claims in 2023 as a Gastroenterology Physician in Lancaster, Pennsylvania, prescribing 82% generic.

251
Part D claims, 2023
82%
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.

John Horwhat, M.D.'s Medicare Part D volume vs every U.S. prescriber

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

251 49th percentile higher than 49% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). This entry sits in this band. 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 certification likely (heuristic, not verified)

John Horwhat, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 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 John Horwhat, M.D.?

Quality data not reported

NPI registry status

Active

Issued 10/02/2006

NPI 1487747242

Primary specialty

Gastroenterology Physician

Mid-sized

16,601 US NPIs in this specialty

Medicare Part D claims

251 70% vs specialty avg

2023 prescription claims

Specialty avg: 833

Specialty distribution in Pennsylvania

How Gastroenterology Physician compares to other specialties among Pennsylvania providers

Pennsylvania providers
Student in an Organized Health Care Education/Training Program - 5.6%Student in an Organized Health Care Education/Training Program5.6%Pharmacist - 5%Pharmacist5%Physical Therapist - 4.9%Physical Therapist4.9%Mental Health Counselor - 3.9%Mental Health Counselor3.9%Internal Medicine Physician - 3.3%Internal Medicine Physician3.3%Professional Counselor - 3.2%Professional Counselor3.2%Gastroenterology Physician - 0.3%Gastroenterology Physician0.3%
Largest specialties in Pennsylvania (% 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 Gastroenterology 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 Horwhat, M.D. appears in the CMS NPPES registry as a Gastroenterology Physician provider holding M.D. credentials at 2112 HARRISBURG PIKE, Lancaster, PA, 17601, with a listed phone of (717) 544-3500. NPI 1487747242 was issued on 10/02/2006.

Medicare Part D records for calendar year 2023 show 251 prescription claims written by this provider, covering 102 Medicare beneficiaries and totaling roughly $132K in drug spend, split 18% brand-name and 82% generic by claim count.

Gastroenterology Physician is a mid-sized specialty nationwide, with 16,601 enrolled providers across 54 states and an average of 833 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

2112 HARRISBURG PIKE
Lancaster, PA 17601

Provider Details

NPI 1487747242
Specialty Gastroenterology Physician
Credentials M.D.
Gender Male
NPI Issued 10/02/2006

Hospital and facility affiliations

Facilities where John Horwhat, 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.

Lancaster General Hospital
★★★★★ 5/5
Lancaster, PA
Acute Care Hospitals
CMS CCN: 390100
Regional Gastroenterology Associates OF Lancaster, Ltd.
Lancaster, PA

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 John Horwhat, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$1.1K

Largest payer

ABBVIE 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 - Pennsylvania PA-BOM 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 ~45K Pennsylvania medical licensees in 2023 - they are NOT specific to John Horwhat, M.D.. To verify John Horwhat, M.D.'s current license status, search the PA-BOM public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

133
Total board actions, Pennsylvania 2023
Across 129 cases
2.96
Actions per 1,000 licensees
Pennsylvania statewide rate
probation
Most common action type
48 cases

PA-BOM 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 Pennsylvania disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Typical

John Horwhat, M.D. - brand share 18.0%
Gastroenterology Physician average

18% brand-name claims vs 82% generic, on 251 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.

251
Total Claims
$132K
Total Drug Cost
102
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
438
Total Day Supply
12,478
Brand vs Generic
18% brand / 82% generic
Brand Drug Cost
$123K
Generic Drug Cost
$8K
Antibiotic Claims
17

Patient Demographics

Average Patient Age
73.4 years
Avg HCC Risk Score
1.67
Gender Split
48% female / 52% male

Top Prescribed Drugs (Medicare Part D)

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

What John Horwhat, 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
Omeprazole
102
Pantoprazole Sodium
29
Creon
Lipase/Protease/Amylase
25
Colestipol Hcl
11
Ursodiol
11

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

Gastroenterology Physician Overview

How John Horwhat, M.D. fits within the Gastroenterology Physician landscape nationally.

16,601
Gastroenterology Physician Providers in US
54
States with Gastroenterology Physician
833
Avg Claims per Provider

John Horwhat, M.D.'s 251 claims are below the specialty average of 833.

Nearby Gastroenterology Physician Providers in Pennsylvania

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

Compare Gastroenterology 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 Pennsylvania medical board, federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Gastroenterology 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 John Horwhat, M.D.'s specialty?
John Horwhat, M.D. specializes in Gastroenterology Physician and practices in Lancaster, Pennsylvania. Credentials: M.D..
How much does John Horwhat, M.D. prescribe under Medicare Part D?
In 2023, John Horwhat, M.D. wrote 251 Medicare Part D claims totaling $132K in drug costs for 102 beneficiaries.
Where is John Horwhat, M.D. located?
John Horwhat, M.D. is located at 2112 HARRISBURG PIKE, Lancaster, PA, 17601. Phone: (717) 544-3500.
What is John Horwhat, M.D.'s NPI number?
John Horwhat, M.D.'s National Provider Identifier (NPI) is 1487747242, issued on 10/02/2006.
Does John Horwhat, M.D. prescribe more brand-name or generic drugs?
John Horwhat, M.D.'s prescribing is 18% brand-name and 82% generic drugs by claim count, with $123K in brand drug costs.
How many Gastroenterology Physician providers are there in the US?
There are 16,601 Gastroenterology Physician providers across 54 states in the US. The average Gastroenterology Physician provider writes 833 Medicare Part D claims per year.
What drugs does John Horwhat, M.D. prescribe most often?
Based on 2023 Medicare Part D data, John Horwhat, M.D.'s most frequently prescribed drugs include Omeprazole, Pantoprazole Sodium, Creon. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does John Horwhat, M.D. accept Medicare?
John Horwhat, M.D. appears in CMS Medicare data with 251 Part D claims and 102 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify John Horwhat, M.D.'s credentials?
John Horwhat, M.D.'s NPI is 1487747242 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.

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.