2026 NPPES data Allergy & Immunology (Internal Medicine) Physician NPI 1366415036 MD
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KENNETH EPSTEIN, MD

Allergy & Immunology (Internal Medicine) Physician in FLAGSTAFF, Arizona. 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
351
Medicare Part D claims · 40 beneficiaries · Allergy & Immunology (Internal Medicine) Physician avg: 798
MIPS score
70.5849/100
▼ 13 pts below national avg 83.1 · [object Object]

What the federal data shows

KENNETH EPSTEIN, MD reported a CMS MIPS final score of 70.5849/100 — below the 83.1 national average — and filed 351 Medicare Part D claims in 2023.

70.5849/100
MIPS score · -13 vs avg
351
Part D claims, 2023
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.

KENNETH EPSTEIN, MD's MIPS score vs every scored U.S. clinician

CMS Merit-based Incentive Payment System (MIPS) final score, 2023 — the federal quality measure

71 8th percentile higher than 8% of 477,587 scored providers

0–10: 8,684 scored providers (2%). Below this entry. 10–20: 3,008 scored providers (1%). Below this entry. 20–30: 3,069 scored providers (1%). Below this entry. 30–40: 2,746 scored providers (1%). Below this entry. 40–50: 2,928 scored providers (1%). Below this entry. 50–60: 5,882 scored providers (1%). Below this entry. 60–70: 13,906 scored providers (3%). Below this entry. 70–80: 118,074 scored providers (25%). This entry sits in this band. 80–90: 129,887 scored providers (27%). Above this entry. 90–100: 189,403 scored providers (40%). Above this entry. This provider 0 100 every MIPS-scored clinician, bucketed by value

Each bar is a band; taller bars hold more scored 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.

Source CMS Merit-based Incentive Payment System (MIPS) · 2023

Board certification likely (heuristic — not verified)

KENNETH EPSTEIN, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting — 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 KENNETH EPSTEIN, MD?

Below national average

NPI registry status

Active

Issued 02/10/2006

NPI 1366415036

Primary specialty

Allergy & Immunology (Internal Medicine) Physician

Niche

520 US NPIs in this specialty

Medicare Part D claims

351 56% vs specialty avg

2023 prescription claims

Specialty avg: 798

MIPS final score

70.5849/100 12.51509999999999% pts

Mid-tier band

vs 83.1 national avg

Specialty distribution in Arizona

How Allergy & Immunology (Internal Medicine) Physician compares to other specialties among Arizona providers

Arizona providers

Allergy & Immunology (Internal Medicine) Physician share within Arizona

1. Allergy & Immunology (Internal Medicine) Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Allergy & Immunology (Internal Medicine) Physician share within Arizona

Medicare quality performance — MIPS

KENNETH EPSTEIN, MD's 2023 MIPS final score plotted against the Allergy & Immunology (Internal Medicine) Physician national average

Below national average
MIPS Final Score
70.5849/100
vs 83.1 national avg · 2023 performance year

MIPS final score (Allergy & Immunology (Internal Medicine) Physician) — 70.5849/100 vs national avg 83.1

0%100%National avg83%70.6%
MIPS final score (Allergy & Immunology (Internal Medicine) Physician) — 70.5849/100 vs national avg 83.1

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).

KENNETH EPSTEIN, MD appears in the CMS NPPES registry as a Allergy & Immunology (Internal Medicine) Physician provider holding MD credentials at 1338 W FOREST MEADOWS ST, FLAGSTAFF, AZ, 86001, with a listed phone of (928) 213-8631. NPI 1366415036 was issued on 02/10/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what EPSTEIN 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 351 prescription claims written by this provider, covering 40 Medicare beneficiaries and totaling roughly $643K in drug spend. 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. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 70.5849/100 for the 2023 performance year (Quality 39.6808, Cost 63.1023), compared with the national average of 83.1.

Allergy & Immunology (Internal Medicine) Physician is a narrow specialty nationwide, with 520 enrolled providers across 48 states and an average of 798 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

1338 W FOREST MEADOWS ST
FLAGSTAFF, AZ 86001

Provider Details

NPI 1366415036
Specialty Allergy & Immunology (Internal Medicine) Physician
Credentials MD
Gender Male
NPI Issued 02/10/2006

CMS Quality Score (MIPS)

Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.

70.5849
Final Score
Avg: 83.1
39.6808
Quality
63.1023
Cost
79
Promoting Interoperability

Reporting: Group practice

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

351
Total Claims
$643K
Total Drug Cost
40
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
352
Total Day Supply
10,190
Generic Drug Cost
$9K

Patient Demographics

Average Patient Age
69.4 years
Avg HCC Risk Score
1.40
Age Distribution
<65: 13, 65-74: N/A, 75-84: 14, 85+: N/A

Top Prescribed Drugs (Medicare Part D)

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

What KENNETH EPSTEIN, MD 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
Prednisone
61
Hydroxychloroquine Sulfate
47
Humira Pen
Adalimumab
29
Methotrexate
Methotrexate Sodium
28
Enbrel
Etanercept
26
Leflunomide
25
Folic Acid
18
Lisinopril
16
Leucovorin Calcium
12
Sulfasalazine Dr
Sulfasalazine
12

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

Allergy & Immunology (Internal Medicine) Physician Overview

How KENNETH EPSTEIN, MD fits within the Allergy & Immunology (Internal Medicine) Physician landscape nationally.

520
Allergy & Immunology (Internal Medicine) Physician Providers in US
48
States with Allergy & Immunology (Internal Medicine) Physician
798
Avg Claims per Provider

KENNETH EPSTEIN, MD's 351 claims are below the specialty average of 798.

Nearby Allergy & Immunology (Internal Medicine) Physician Providers in Arizona

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

Compare Allergy & Immunology (Internal Medicine) Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is KENNETH EPSTEIN, MD's specialty?
KENNETH EPSTEIN, MD specializes in Allergy & Immunology (Internal Medicine) Physician and practices in FLAGSTAFF, Arizona. Credentials: MD.
How much does KENNETH EPSTEIN, MD prescribe under Medicare Part D?
In 2023, KENNETH EPSTEIN, MD wrote 351 Medicare Part D claims totaling $643K in drug costs for 40 beneficiaries.
What is KENNETH EPSTEIN, MD's Medicare quality score?
KENNETH EPSTEIN, MD has a CMS MIPS Final Score of 70.5849/100 (Quality: 39.6808, Cost: 63.1023). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is KENNETH EPSTEIN, MD located?
KENNETH EPSTEIN, MD is located at 1338 W FOREST MEADOWS ST, FLAGSTAFF, AZ, 86001. Phone: (928) 213-8631.
What is KENNETH EPSTEIN, MD's NPI number?
KENNETH EPSTEIN, MD's National Provider Identifier (NPI) is 1366415036, issued on 02/10/2006.
How many Allergy & Immunology (Internal Medicine) Physician providers are there in the US?
There are 520 Allergy & Immunology (Internal Medicine) Physician providers across 48 states in the US. The average Allergy & Immunology (Internal Medicine) Physician provider writes 798 Medicare Part D claims per year.
What drugs does KENNETH EPSTEIN, MD prescribe most often?
Based on 2023 Medicare Part D data, KENNETH EPSTEIN, MD's most frequently prescribed drugs include Prednisone, Hydroxychloroquine Sulfate, Humira Pen. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does KENNETH EPSTEIN, MD accept Medicare?
KENNETH EPSTEIN, MD appears in CMS Medicare data with 351 Part D claims and 40 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify KENNETH EPSTEIN, MD's credentials?
KENNETH EPSTEIN, MD's NPI is 1366415036 with credentials MD. 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.
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