NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1881636777 D.O.
Verify on CMS → Phat Nguyen, D.O.
Internal Medicine Physician in Manchester, New Hampshire.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 172,737 in Internal Medicine 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
7K
Medicare Part D claims · 550 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
90%
generic claims · 10% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
81.6/100
▼ 1 pts below national avg 83.1 · Above neutral
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
Phat Nguyen, D.O. reported a CMS MIPS final score of 81.6/100 - below the 83.1 national average - and filed 6,742 Medicare Part D claims in 2023.
- 81.6/100
- MIPS score · -1 vs avg
- 7K
- 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.
Phat Nguyen, D.O.'s MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
82 36th percentile higher than 36% 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 Phat Nguyen, D.O. sits
This provider among internal medicine physician peers
Across the 36,260 internal medicine physician providers who report both Medicare Part D prescribing and a MIPS quality score, Phat Nguyen, D.O. writes more Part D claims than 85% of them and scores higher on MIPS quality than 37% - placing this provider in the high-volume, lower-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 internal medicine physician peer from a representative sample of 60; the gold marker is Phat Nguyen, D.O.. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
Phat Nguyen, D.O. 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 Phat Nguyen, D.O.?
Near national averagePrimary specialty
Internal Medicine Physician
Medicare Part D claims
6,742 148% vs specialty avg
MIPS final score
81.6/100 1.5 pts vs avg
Specialty distribution in New Hampshire
How Internal Medicine Physician compares to other specialties among New Hampshire providers
Medicare quality performance, MIPS
Phat Nguyen, D.O.'s 2023 MIPS final score plotted against the Internal Medicine Physician national average
- MIPS Final Score
- 81.6/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Internal Medicine Physician) - 81.6/100 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).
Phat Nguyen, D.O. appears in the CMS NPPES registry as an Internal Medicine Physician provider holding D.O. credentials at 100 HITCHCOCK WAY, Manchester, NH, 03104, with a listed phone of (603) 695-2500. NPI 1881636777 was issued on 06/12/2006.
Medicare Part D records for calendar year 2023 show 6,742 prescription claims written by this provider, covering 550 Medicare beneficiaries and totaling roughly $650K in drug spend, split 10% brand-name and 90% generic by claim count. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 81.6/100 for the 2023 performance year (Quality 79.1, Cost 59.7), compared with the national average of 83.1.
Internal Medicine Physician is a high-volume specialty nationwide, with 172,737 enrolled providers across 56 states and an average of 2,716 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 | 1881636777 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | D.O. |
| Gender | Male |
| NPI Issued | 06/12/2006 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
81.6481
Final Score
Avg: 83.1
79.0846
Quality
59.7424
Cost
100
Promoting Interoperability
Reporting: Group practice
Brand vs generic prescribing mix · Typical
Phat Nguyen, D.O. - brand share 10.0%
Internal Medicine Physician average
10% brand-name claims vs 90% generic, on 6,742 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.
6,742
Total Claims
$650K
Total Drug Cost
550
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 17,143
- Total Day Supply
- 507,452
- Brand vs Generic
- 10% brand / 90% generic
- Brand Drug Cost
- $527K
- Generic Drug Cost
- $121K
- Antibiotic Claims
- 42
Patient Demographics
- Average Patient Age
- 71.8 years
- Avg HCC Risk Score
- 1.08
- Gender Split
- 32% female / 68% male
- Age Distribution
- <65: 63, 65-74: 279, 75-84: 175, 85+: 33
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Phat Nguyen, D.O. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
654 claims
- Lisinopril
Lisinopril
495 claims
- Amlodipine Besylate
Amlodipine Besylate
394 claims
- Losartan Potassium
Losartan Potassium
392 claims
- Levothyroxine Sodium 257
Levothyroxine Sodium
257 claims
- Metformin Hcl Er 247
Metformin Hcl Er
247 claims
- Omeprazole 210
Omeprazole
210 claims
- Metoprolol Succinate 179
Metoprolol Succinate
179 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 654 |
| Lisinopril | 495 |
| Amlodipine Besylate | 394 |
| Losartan Potassium | 392 |
| Levothyroxine Sodium | 257 |
| Metformin Hcl Er Metformin Hcl | 247 |
| Omeprazole | 210 |
| Metoprolol Succinate | 179 |
| Hydrochlorothiazide | 156 |
| Pantoprazole Sodium | 149 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Internal Medicine Physician Overview
How Phat Nguyen, D.O. fits within the Internal Medicine Physician landscape nationally.
172,737
Internal Medicine Physician Providers in US
56
States with Internal Medicine Physician
2,716
Avg Claims per Provider
Phat Nguyen, D.O.'s 6,742 claims are above the specialty average of 2,716.
Nearby Internal Medicine Physician Providers in New Hampshire
Other clinicians with the same primary specialty enrolled in New Hampshire, drawn from the same CMS NPPES roster as Nguyen.
Dr. Lauren Abbott
MD
Portsmouth, NH
Dr. Cherif Abdelmalek
M.D.
Nashua, NH
Dr. Champa Abeysinghe
M.D.
New London, NH
Dr. Suzanne Abkowitz
MD
North Conway, NH
Dr. Arthur Ablayev
MD
Concord, NH
Compare Internal Medicine 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 Hampshire medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Internal Medicine 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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Explore New Hampshire
Frequently Asked Questions
What is Phat Nguyen, D.O.'s specialty? ▼
Phat Nguyen, D.O. specializes in Internal Medicine Physician and practices in Manchester, New Hampshire. Credentials: D.O..
How much does Phat Nguyen, D.O. prescribe under Medicare Part D? ▼
In 2023, Phat Nguyen, D.O. wrote 6,742 Medicare Part D claims totaling $650K in drug costs for 550 beneficiaries.
What is Phat Nguyen, D.O.'s Medicare quality score? ▼
Phat Nguyen, D.O. has a CMS MIPS Final Score of 81.6/100 (Quality: 79.1, Cost: 59.7). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Phat Nguyen, D.O. located? ▼
Phat Nguyen, D.O. is located at 100 HITCHCOCK WAY, Manchester, NH, 03104. Phone: (603) 695-2500.
What is Phat Nguyen, D.O.'s NPI number? ▼
Phat Nguyen, D.O.'s National Provider Identifier (NPI) is 1881636777, issued on 06/12/2006.
Does Phat Nguyen, D.O. prescribe more brand-name or generic drugs? ▼
Phat Nguyen, D.O.'s prescribing is 10% brand-name and 90% generic drugs by claim count, with $527K in brand drug costs.
How many Internal Medicine Physician providers are there in the US? ▼
There are 172,737 Internal Medicine Physician providers across 56 states in the US. The average Internal Medicine Physician provider writes 2,716 Medicare Part D claims per year.
What drugs does Phat Nguyen, D.O. prescribe most often? ▼
Based on 2023 Medicare Part D data, Phat Nguyen, D.O.'s most frequently prescribed drugs include Atorvastatin Calcium, Lisinopril, Amlodipine Besylate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Phat Nguyen, D.O. accept Medicare? ▼
Phat Nguyen, D.O. appears in CMS Medicare data with 6,742 Part D claims and 550 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Phat Nguyen, D.O.'s credentials? ▼
Phat Nguyen, D.O.'s NPI is 1881636777 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
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.
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.