2026 NPPES data Dermatology Physician NPI 1326163890 D.O.
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GREGORY GANZER, D.O.

Dermatology Physician in WHEELING, West Virginia. 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
1K
Medicare Part D claims · 361 beneficiaries · Dermatology Physician avg: 729
Generic prescribing
90%
generic claims · 10% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

GREGORY GANZER, D.O. filed 1,255 Medicare Part D claims in 2023 as a Dermatology Physician in WHEELING, West Virginia, prescribing 90% generic.

1K
Part D claims, 2023
90%
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.

GREGORY GANZER, D.O.'s Medicare Part D volume vs every U.S. prescriber

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

1,255 Top 22% higher than 78% 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%). This entry sits in this band. 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. 2,000–2,200: 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)

GREGORY GANZER, D.O. 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 GANZER, D.O.?

Quality data not reported

NPI registry status

Active

Issued 03/21/2007

NPI 1326163890

Primary specialty

Dermatology Physician

Mid-sized

14,610 US NPIs in this specialty

Medicare Part D claims

1,255 72% vs specialty avg

2023 prescription claims

Specialty avg: 729

Specialty distribution in West Virginia

How Dermatology Physician compares to other specialties among West Virginia providers

West Virginia providers

Dermatology Physician share within West Virginia

1. Dermatology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Dermatology Physician share within West Virginia

Specialty board-certification context

Estimated specialty board-certified rate — Dermatology Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Dermatology Physician ABMS/AOA estimate

Est. board-certified rate (Dermatology Physician) — ABMS / AOA estimate

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

GREGORY GANZER, D.O. appears in the CMS NPPES registry as a Dermatology Physician provider holding D.O. credentials at 2101 CHAPLINE ST, WHEELING, WV, 26003, with a listed phone of (304) 233-3240. NPI 1326163890 was issued on 03/21/2007. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GANZER 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 1,255 prescription claims written by this provider, covering 361 Medicare beneficiaries and totaling roughly $776K in drug spend, split 10% brand-name and 90% generic by claim count. 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.

Dermatology Physician is a mid-sized specialty nationwide, with 14,610 enrolled providers across 53 states and an average of 729 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

2101 CHAPLINE ST
WHEELING, WV 26003

Provider Details

NPI 1326163890
Specialty Dermatology Physician
Credentials D.O.
Gender Male
NPI Issued 03/21/2007

Hospital and facility affiliations

Facilities where GREGORY GANZER, D.O. 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.

GANZER - HAHN DERMATOLOGY ASSOCIATES, PLLC
WHEELING, WV

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Brand vs generic prescribing mix · Typical

GREGORY GANZER, D.O. — brand share 10.0%
Specialty average (est.)

10% brand-name claims vs 90% generic, on 1,255 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.

1,255
Total Claims
$776K
Total Drug Cost
361
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,285
Total Day Supply
31,201
Brand vs Generic
10% brand / 90% generic
Brand Drug Cost
$749K
Generic Drug Cost
$27K
Antibiotic Claims
170

Patient Demographics

Average Patient Age
72.0 years
Avg HCC Risk Score
1.28
Gender Split
52% female / 48% male
Age Distribution
<65: 50, 65-74: 159, 75-84: 111, 85+: 41

Top Prescribed Drugs (Medicare Part D)

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

What GREGORY GANZER, D.O. 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
Triamcinolone Acetonide
291
Ketoconazole
131
Mupirocin
123
Prednisone
71
Otezla
Apremilast
52
Minocycline Hcl
48
Hydroxyzine Hcl
45
Clobetasol Propionate
44
Betamethasone Dipropionate
43
Cephalexin
32

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

Dermatology Physician Overview

How GREGORY GANZER, D.O. fits within the Dermatology Physician landscape nationally.

14,610
Dermatology Physician Providers in US
53
States with Dermatology Physician
729
Avg Claims per Provider

GREGORY GANZER, D.O.'s 1,255 claims are above the specialty average of 729.

Nearby Dermatology Physician Providers in West Virginia

Other clinicians with the same primary specialty enrolled in West Virginia, drawn from the same CMS NPPES roster as GANZER.

Compare Dermatology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is GREGORY GANZER, D.O.'s specialty?
GREGORY GANZER, D.O. specializes in Dermatology Physician and practices in WHEELING, West Virginia. Credentials: D.O..
How much does GREGORY GANZER, D.O. prescribe under Medicare Part D?
In 2023, GREGORY GANZER, D.O. wrote 1,255 Medicare Part D claims totaling $776K in drug costs for 361 beneficiaries.
Where is GREGORY GANZER, D.O. located?
GREGORY GANZER, D.O. is located at 2101 CHAPLINE ST, WHEELING, WV, 26003. Phone: (304) 233-3240.
What is GREGORY GANZER, D.O.'s NPI number?
GREGORY GANZER, D.O.'s National Provider Identifier (NPI) is 1326163890, issued on 03/21/2007.
Does GREGORY GANZER, D.O. prescribe more brand-name or generic drugs?
GREGORY GANZER, D.O.'s prescribing is 10% brand-name and 90% generic drugs by claim count, with $749K in brand drug costs.
How many Dermatology Physician providers are there in the US?
There are 14,610 Dermatology Physician providers across 53 states in the US. The average Dermatology Physician provider writes 729 Medicare Part D claims per year.
What drugs does GREGORY GANZER, D.O. prescribe most often?
Based on 2023 Medicare Part D data, GREGORY GANZER, D.O.'s most frequently prescribed drugs include Triamcinolone Acetonide, Ketoconazole, Mupirocin. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does GREGORY GANZER, D.O. accept Medicare?
GREGORY GANZER, D.O. appears in CMS Medicare data with 1,255 Part D claims and 361 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify GREGORY GANZER, D.O.'s credentials?
GREGORY GANZER, D.O.'s NPI is 1326163890 with credentials D.O.. 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