NPI registry status
Active
2026 NPPES data Gastroenterology Physician NPI 1720077944 M.D.
Verify on CMS → Iheanyichukwu Aja-Onu, M.D.
Gastroenterology Physician in Freeport, New York.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 16,567 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
639
Medicare Part D claims · 164 beneficiaries · Gastroenterology Physician avg: 833
Generic prescribing
77%
generic claims · 23% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
98.8/100
▲ 16 pts above national avg 83.1 · Exceptional
Industry payments
$1.0K
45 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
Iheanyichukwu Aja-Onu, M.D. reported a CMS MIPS final score of 98.8/100 - above the 83.1 national average - and filed 639 Medicare Part D claims in 2023.
- 98.8/100
- MIPS score · +16 vs avg
- 639
- Part D claims, 2023
- 77%
- 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.
Iheanyichukwu Aja-Onu, M.D.'s MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
99 Top 11% higher than 89% of 477,587 scored providers
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
Where Iheanyichukwu Aja-Onu, M.D. sits
This provider among gastroenterology physician peers
Across the 5,957 gastroenterology physician providers who report both Medicare Part D prescribing and a MIPS quality score, Iheanyichukwu Aja-Onu, M.D. writes more Part D claims than 41% of them and scores higher on MIPS quality than 90% - placing this provider in the lower-volume, high-quality quadrant. Volume reflects patient-panel size and specialty, not quality; the two axes are independent.
Part D claim volume vs MIPS quality, by specialty percentile
Each dot is one gastroenterology physician peer from a representative sample of 60; the gold marker is Iheanyichukwu Aja-Onu, M.D.. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
Iheanyichukwu Aja-Onu, M.D. 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 Iheanyichukwu Aja-Onu, M.D.?
High performer (top quartile)Primary specialty
Gastroenterology Physician
Medicare Part D claims
639 23% vs specialty avg
MIPS final score
98.8/100 15.7 pts vs avg
Specialty distribution in New York
How Gastroenterology Physician compares to other specialties among New York providers
Medicare quality performance, MIPS
Iheanyichukwu Aja-Onu, M.D.'s 2023 MIPS final score plotted against the Gastroenterology Physician national average
- MIPS Final Score
- 98.8/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Gastroenterology Physician) - 98.8/100 vs national avg 83.1
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).
Iheanyichukwu Aja-Onu, M.D. appears in the CMS NPPES registry as a Gastroenterology Physician provider holding M.D. credentials at 3 N MAIN ST, Freeport, NY, 11520, with a listed phone of (516) 623-5076. NPI 1720077944 was issued on 10/20/2005.
Medicare Part D records for calendar year 2023 show 639 prescription claims written by this provider, covering 164 Medicare beneficiaries and totaling roughly $286K in drug spend, split 23% brand-name and 77% generic by claim count. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 98.8/100 for the 2023 performance year (Quality 80.6), compared with the national average of 83.1.
Gastroenterology Physician is a mid-sized specialty nationwide, with 16,567 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
Provider Details
| NPI | 1720077944 |
|---|---|
| Specialty | Gastroenterology Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 10/20/2005 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
98.8187
Final Score
Avg: 83.1
80.6374
Quality
95
Promoting Interoperability
Reporting: Alternative Payment Model
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 Iheanyichukwu Aja-Onu, M.D.. Source: openpaymentsdata.cms.gov.
Total received
$1.0K
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 - New York NYSBPMC 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 ~100K New York medical licensees in 2023 - they are NOT specific to Iheanyichukwu Aja-Onu, M.D.. To verify Iheanyichukwu Aja-Onu, M.D.'s current license status, search the NYSBPMC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.
312
Total board actions, New York 2023
Across 302 cases
3.12
Actions per 1,000 licensees
New York statewide rate
probation
Most common action type
89 cases
NYSBPMC 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 New York disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.
Brand vs generic prescribing mix · Typical
Iheanyichukwu Aja-Onu, M.D. - brand share 23.0%
Gastroenterology Physician average
23% brand-name claims vs 77% generic, on 639 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.
639
Total Claims
$286K
Total Drug Cost
164
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 884
- Total Day Supply
- 25,705
- Brand vs Generic
- 23% brand / 77% generic
- Brand Drug Cost
- $263K
- Generic Drug Cost
- $23K
Patient Demographics
- Average Patient Age
- 72.4 years
- Avg HCC Risk Score
- 1.87
- Gender Split
- 65% female / 35% male
- Age Distribution
- <65: 21, 65-74: 82, 75-84: 40, 85+: 21
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Iheanyichukwu Aja-Onu, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Omeprazole
Omeprazole
141 claims
- Famotidine
Famotidine
79 claims
- Linzess
Linzess
62 claims
- Pantoprazole Sodium 44
Pantoprazole Sodium
44 claims
- Ursodiol 31
Ursodiol
31 claims
- Mirtazapine 16
Mirtazapine
16 claims
- Sulfasalazine 16
Sulfasalazine
16 claims
- Humira(Cf) Pen 12
Humira(Cf) Pen
12 claims
| Drug | Claims |
|---|---|
| Omeprazole | 141 |
| Famotidine | 79 |
| Linzess Linaclotide | 62 |
| Pantoprazole Sodium | 44 |
| Ursodiol | 31 |
| Mirtazapine | 16 |
| Sulfasalazine | 16 |
| Humira(Cf) Pen Adalimumab | 12 |
| Procto-Med Hc Hydrocortisone | 12 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Gastroenterology Physician Overview
How Iheanyichukwu Aja-Onu, M.D. fits within the Gastroenterology Physician landscape nationally.
16,567
Gastroenterology Physician Providers in US
54
States with Gastroenterology Physician
833
Avg Claims per Provider
Iheanyichukwu Aja-Onu, M.D.'s 639 claims are below the specialty average of 833.
Nearby Gastroenterology Physician Providers in New York
Other clinicians with the same primary specialty enrolled in New York, drawn from the same CMS NPPES roster as Aja-Onu.
Dr. Elie Abadie
MD
Brooklyn, NY
Dr. Hafsa Abbas
MD
Flushing, NY
Dr. Naeem Abbas
MD
Valley Stream, NY
Dr. Uzma Abbasi
M.D.
Oneida, NY
Amro Abdellatief
New York, NY
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 New York 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.
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Frequently Asked Questions
What is Iheanyichukwu Aja-Onu, M.D.'s specialty? ▼
Iheanyichukwu Aja-Onu, M.D. specializes in Gastroenterology Physician and practices in Freeport, New York. Credentials: M.D..
How much does Iheanyichukwu Aja-Onu, M.D. prescribe under Medicare Part D? ▼
In 2023, Iheanyichukwu Aja-Onu, M.D. wrote 639 Medicare Part D claims totaling $286K in drug costs for 164 beneficiaries.
What is Iheanyichukwu Aja-Onu, M.D.'s Medicare quality score? ▼
Iheanyichukwu Aja-Onu, M.D. has a CMS MIPS Final Score of 98.8/100 (Quality: 80.6). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Iheanyichukwu Aja-Onu, M.D. located? ▼
Iheanyichukwu Aja-Onu, M.D. is located at 3 N MAIN ST, Freeport, NY, 11520. Phone: (516) 623-5076.
What is Iheanyichukwu Aja-Onu, M.D.'s NPI number? ▼
Iheanyichukwu Aja-Onu, M.D.'s National Provider Identifier (NPI) is 1720077944, issued on 10/20/2005.
Does Iheanyichukwu Aja-Onu, M.D. prescribe more brand-name or generic drugs? ▼
Iheanyichukwu Aja-Onu, M.D.'s prescribing is 23% brand-name and 77% generic drugs by claim count, with $263K in brand drug costs.
How many Gastroenterology Physician providers are there in the US? ▼
There are 16,567 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 Iheanyichukwu Aja-Onu, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Iheanyichukwu Aja-Onu, M.D.'s most frequently prescribed drugs include Omeprazole, Famotidine, Linzess. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Iheanyichukwu Aja-Onu, M.D. accept Medicare? ▼
Iheanyichukwu Aja-Onu, M.D. appears in CMS Medicare data with 639 Part D claims and 164 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Iheanyichukwu Aja-Onu, M.D.'s credentials? ▼
Iheanyichukwu Aja-Onu, M.D.'s NPI is 1720077944 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.
- 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
Compiled from official public sources by the PlainDoctor editorial team.