2026 NPPES data Family Medicine Physician NPI 1639751407
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KOSTANTINOS PAPATHANASIOU

Family Medicine Physician in SPRINGFIELD, Massachusetts. 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
443
Medicare Part D claims · 51 beneficiaries · Family Medicine Physician avg: 3K
Generic prescribing
83%
generic claims · 17% brand-name · higher generic rates reduce patient out-of-pocket costs

What the federal data shows

KOSTANTINOS PAPATHANASIOU filed 443 Medicare Part D claims in 2023 as a Family Medicine Physician in SPRINGFIELD, Massachusetts, prescribing 83% generic.

443
Part D claims, 2023
83%
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.

KOSTANTINOS PAPATHANASIOU's Medicare Part D volume vs every U.S. prescriber

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

443 Top 38% higher than 62% 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%). This entry sits in this band. 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. 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-eligible specialty (heuristic — not verified)

KOSTANTINOS PAPATHANASIOU 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 KOSTANTINOS PAPATHANASIOU?

Quality data not reported

NPI registry status

Active

Issued 04/22/2021

NPI 1639751407

Primary specialty

Family Medicine Physician

High-volume

147,640 US NPIs in this specialty

Medicare Part D claims

443 87% vs specialty avg

2023 prescription claims

Specialty avg: 3,418

Specialty distribution in Massachusetts

How Family Medicine Physician compares to other specialties among Massachusetts providers

Massachusetts providers

Family Medicine Physician share within Massachusetts

1. Family Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Family Medicine Physician share within Massachusetts

Specialty board-certification context

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

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

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

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

KOSTANTINOS PAPATHANASIOU appears in the CMS NPPES registry as a Family Medicine Physician provider at 819 WORCESTER ST, SPRINGFIELD, MA, 01151, with a listed phone of (337) 991-9276. NPI 1639751407 was issued on 04/22/2021. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what PAPATHANASIOU 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 443 prescription claims written by this provider, covering 51 Medicare beneficiaries and totaling roughly $44K in drug spend, split 17% brand-name and 83% 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.

Family Medicine Physician is a high-volume specialty nationwide, with 147,640 enrolled providers across 56 states and an average of 3,418 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

819 WORCESTER ST
SPRINGFIELD, MA 01151

Provider Details

NPI 1639751407
Specialty Family Medicine Physician
Gender Male
NPI Issued 04/22/2021

License & disciplinary context — Massachusetts BORIM 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 ~38K Massachusetts medical licensees in 2023 — they are NOT specific to KOSTANTINOS PAPATHANASIOU. To verify KOSTANTINOS PAPATHANASIOU's current license status, search the BORIM public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

80
Total board actions, Massachusetts 2023
Across 78 cases
2.11
Actions per 1,000 licensees
Massachusetts statewide rate
probation
Most common action type
29 cases

BORIM 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 Massachusetts disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Brand vs generic prescribing mix · Typical

KOSTANTINOS PAPATHANASIOU — brand share 17.0%
Specialty average (est.)

17% brand-name claims vs 83% generic, on 443 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.

443
Total Claims
$44K
Total Drug Cost
51
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
641
Total Day Supply
17,617
Brand vs Generic
17% brand / 83% generic
Brand Drug Cost
$36K
Generic Drug Cost
$8K

Patient Demographics

Average Patient Age
64.0 years
Avg HCC Risk Score
1.73
Gender Split
55% female / 45% male
Age Distribution
<65: 23, 65-74: 21, 75-84: N/A, 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 KOSTANTINOS PAPATHANASIOU 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
Levothyroxine Sodium
33
Metformin Hcl
24
Albuterol Sulfate Hfa
Albuterol Sulfate
22
Atorvastatin Calcium
20
Gabapentin
20
Lisinopril
16
Omeprazole
15
Tamsulosin Hcl
14
Quetiapine Fumarate
13
Buprenorphine-Naloxone
Buprenorphine Hcl/Naloxone Hcl
12

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

Family Medicine Physician Overview

How KOSTANTINOS PAPATHANASIOU fits within the Family Medicine Physician landscape nationally.

147,640
Family Medicine Physician Providers in US
56
States with Family Medicine Physician
3,418
Avg Claims per Provider

KOSTANTINOS PAPATHANASIOU's 443 claims are below the specialty average of 3,418.

Nearby Family Medicine Physician Providers in Massachusetts

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

Compare Family Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is KOSTANTINOS PAPATHANASIOU's specialty?
KOSTANTINOS PAPATHANASIOU specializes in Family Medicine Physician and practices in SPRINGFIELD, Massachusetts.
How much does KOSTANTINOS PAPATHANASIOU prescribe under Medicare Part D?
In 2023, KOSTANTINOS PAPATHANASIOU wrote 443 Medicare Part D claims totaling $44K in drug costs for 51 beneficiaries.
Where is KOSTANTINOS PAPATHANASIOU located?
KOSTANTINOS PAPATHANASIOU is located at 819 WORCESTER ST, SPRINGFIELD, MA, 01151. Phone: (337) 991-9276.
What is KOSTANTINOS PAPATHANASIOU's NPI number?
KOSTANTINOS PAPATHANASIOU's National Provider Identifier (NPI) is 1639751407, issued on 04/22/2021.
Does KOSTANTINOS PAPATHANASIOU prescribe more brand-name or generic drugs?
KOSTANTINOS PAPATHANASIOU's prescribing is 17% brand-name and 83% generic drugs by claim count, with $36K in brand drug costs.
How many Family Medicine Physician providers are there in the US?
There are 147,640 Family Medicine Physician providers across 56 states in the US. The average Family Medicine Physician provider writes 3,418 Medicare Part D claims per year.
What drugs does KOSTANTINOS PAPATHANASIOU prescribe most often?
Based on 2023 Medicare Part D data, KOSTANTINOS PAPATHANASIOU's most frequently prescribed drugs include Levothyroxine Sodium, Metformin Hcl, Albuterol Sulfate Hfa. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does KOSTANTINOS PAPATHANASIOU accept Medicare?
KOSTANTINOS PAPATHANASIOU appears in CMS Medicare data with 443 Part D claims and 51 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify KOSTANTINOS PAPATHANASIOU's credentials?
KOSTANTINOS PAPATHANASIOU's NPI is 1639751407. 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