NPI registry status
Active
2026 NPPES data Nurse Practitioner NPI 1639808603 MSN, A-GNP-C, OCN
Verify on CMS → Katie Iadonisi, MSN, A-GNP-C, OCN
Nurse Practitioner in South Weymouth, Massachusetts.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 87,700 in Nurse Practitioner, 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
297
Medicare Part D claims · 109 beneficiaries · Nurse Practitioner avg: 1K
Generic prescribing
76%
generic claims · 24% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$113.18
5 payments · CMS Open Payments (Sunshine Act)
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
Katie Iadonisi, MSN, A-GNP-C, OCN filed 297 Medicare Part D claims in 2023 as a Nurse Practitioner in South Weymouth, Massachusetts, prescribing 76% generic.
- 297
- Part D claims, 2023
- 76%
- generic prescribing
- $113.18
- industry payments (Sunshine Act)
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.
Katie Iadonisi, MSN, A-GNP-C, OCN's Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
297 49th percentile higher than 49% 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
What does the federal data show about Katie Iadonisi, MSN, A-GNP-C, OCN?
Quality data not reportedPrimary specialty
Nurse Practitioner
Medicare Part D claims
297 73% vs specialty avg
Specialty distribution in Massachusetts
How Nurse Practitioner compares to other specialties among Massachusetts 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 Nurse Practitioner. 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).
Katie Iadonisi, MSN, A-GNP-C, OCN appears in the CMS NPPES registry as a Nurse Practitioner provider holding MSN, A-GNP-C, OCN credentials at 101 COLUMBIAN ST, South Weymouth, MA, 02190, with a listed phone of (781) 624-4800. NPI 1639808603 was issued on 06/06/2022.
Medicare Part D records for calendar year 2023 show 297 prescription claims written by this provider, covering 109 Medicare beneficiaries and totaling roughly $578K in drug spend, split 24% brand-name and 76% generic by claim count, with an opioid prescribing rate of 20.9%.
Nurse Practitioner is a high-volume specialty nationwide, with 87,700 enrolled providers across 56 states and an average of 1,084 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 | 1639808603 |
|---|---|
| Specialty | Nurse Practitioner |
| Credentials | MSN, A-GNP-C, OCN |
| Gender | Female |
| NPI Issued | 06/06/2022 |
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 Katie Iadonisi, MSN, A-GNP-C, OCN. Source: openpaymentsdata.cms.gov.
Total received
$113
Largest payer
TAIHO ONCOLOGY, 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 - 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 Katie Iadonisi, MSN, A-GNP-C, OCN. To verify Katie Iadonisi, MSN, A-GNP-C, OCN'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
Katie Iadonisi, MSN, A-GNP-C, OCN - brand share 24.0%
Nurse Practitioner average
24% brand-name claims vs 76% generic, on 297 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.
297
Total Claims
$578K
Total Drug Cost
109
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 359
- Total Day Supply
- 8,754
- Brand vs Generic
- 24% brand / 76% generic
- Brand Drug Cost
- $492K
- Generic Drug Cost
- $86K
- Opioid Claims
- 62 (20.9% rate)
Patient Demographics
- Average Patient Age
- 72.7 years
- Avg HCC Risk Score
- 2.37
- Gender Split
- 46% female / 54% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Katie Iadonisi, MSN, A-GNP-C, OCN prescribes most
Top Medicare Part D drugs by claim count, 2023
- Oxycodone Hcl
Oxycodone Hcl
36 claims
- Eliquis
Eliquis
22 claims
- Abiraterone Acetate 14
Abiraterone Acetate
14 claims
- Gabapentin 13
Gabapentin
13 claims
- Omeprazole 11
Omeprazole
11 claims
| Drug | Claims |
|---|---|
| Oxycodone Hcl | 36 |
| Eliquis Apixaban | 22 |
| Abiraterone Acetate | 14 |
| Gabapentin | 13 |
| Omeprazole | 11 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Nurse Practitioner Overview
How Katie Iadonisi, MSN, A-GNP-C, OCN fits within the Nurse Practitioner landscape nationally.
87,700
Nurse Practitioner Providers in US
56
States with Nurse Practitioner
1,084
Avg Claims per Provider
Katie Iadonisi, MSN, A-GNP-C, OCN's 297 claims are below the specialty average of 1,084.
Nearby Nurse Practitioner Providers in Massachusetts
Other clinicians with the same primary specialty enrolled in Massachusetts, drawn from the same CMS NPPES roster as Iadonisi.
Dr. Carolyn Abbanat Villafane
NP
Boston, MA
Dr. Lisa Abbondanza
CNP
Franklin, MA
Fatima Abdalla
Melrose, MA
Dr. Esayas Abraham
NP
Chelsea, MA
Alissa Abrahamson
Framingham, MA
Compare Nurse Practitioner 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 Massachusetts medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Nurse Practitioner 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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Frequently Asked Questions
What is Katie Iadonisi, MSN, A-GNP-C, OCN's specialty? ▼
Katie Iadonisi, MSN, A-GNP-C, OCN specializes in Nurse Practitioner and practices in South Weymouth, Massachusetts. Credentials: MSN, A-GNP-C, OCN.
How much does Katie Iadonisi, MSN, A-GNP-C, OCN prescribe under Medicare Part D? ▼
In 2023, Katie Iadonisi, MSN, A-GNP-C, OCN wrote 297 Medicare Part D claims totaling $578K in drug costs for 109 beneficiaries.
Where is Katie Iadonisi, MSN, A-GNP-C, OCN located? ▼
Katie Iadonisi, MSN, A-GNP-C, OCN is located at 101 COLUMBIAN ST, South Weymouth, MA, 02190. Phone: (781) 624-4800.
What is Katie Iadonisi, MSN, A-GNP-C, OCN's NPI number? ▼
Katie Iadonisi, MSN, A-GNP-C, OCN's National Provider Identifier (NPI) is 1639808603, issued on 06/06/2022.
Does Katie Iadonisi, MSN, A-GNP-C, OCN prescribe more brand-name or generic drugs? ▼
Katie Iadonisi, MSN, A-GNP-C, OCN's prescribing is 24% brand-name and 76% generic drugs by claim count, with $492K in brand drug costs.
Does Katie Iadonisi, MSN, A-GNP-C, OCN prescribe opioids? ▼
Yes, Katie Iadonisi, MSN, A-GNP-C, OCN had 62 opioid claims in 2023 with an opioid prescribing rate of 20.9%.
How many Nurse Practitioner providers are there in the US? ▼
There are 87,700 Nurse Practitioner providers across 56 states in the US. The average Nurse Practitioner provider writes 1,084 Medicare Part D claims per year.
What drugs does Katie Iadonisi, MSN, A-GNP-C, OCN prescribe most often? ▼
Based on 2023 Medicare Part D data, Katie Iadonisi, MSN, A-GNP-C, OCN's most frequently prescribed drugs include Oxycodone Hcl, Eliquis, Abiraterone Acetate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Katie Iadonisi, MSN, A-GNP-C, OCN accept Medicare? ▼
Katie Iadonisi, MSN, A-GNP-C, OCN appears in CMS Medicare data with 297 Part D claims and 109 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Katie Iadonisi, MSN, A-GNP-C, OCN's credentials? ▼
Katie Iadonisi, MSN, A-GNP-C, OCN's NPI is 1639808603 with credentials MSN, A-GNP-C, OCN. 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.