NPI registry status
Active
2026 NPPES data Critical Care Medicine (Internal Medicine) Physician NPI 1831181189 MD
Verify on CMS → Sunil Natrajan, MD
Critical Care Medicine (Internal Medicine) Physician in Tucson, Arizona.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 6,631 in Critical Care Medicine (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
998
Medicare Part D claims · 200 beneficiaries · Critical Care Medicine (Internal Medicine) Physician avg: 1K
Generic prescribing
0%
generic claims · 56% brand-name · higher generic rates reduce patient out-of-pocket costs
MIPS score
23.9/100
▼ 59 pts below national avg 83.1 · Below average
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
Sunil Natrajan, MD reported a CMS MIPS final score of 23.9/100 - below the 83.1 national average - and filed 998 Medicare Part D claims in 2023.
- 23.9/100
- MIPS score · -59 vs avg
- 998
- Part D claims, 2023
- 0%
- 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.
Sunil Natrajan, MD's MIPS score vs every scored U.S. clinician
CMS Merit-based Incentive Payment System (MIPS) final score, 2023, the federal quality measure
24 3rd percentile higher than 3% 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 Sunil Natrajan, MD sits
This provider among critical care medicine (internal medicine) physician peers
Across the 1,643 critical care medicine (internal medicine) physician providers who report both Medicare Part D prescribing and a MIPS quality score, Sunil Natrajan, MD writes more Part D claims than 59% of them and scores higher on MIPS quality than 3% - 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 critical care medicine (internal medicine) physician peer from a representative sample of 60; the gold marker is Sunil Natrajan, MD. Source: CMS Medicare Part D Prescriber data and the CMS Merit-based Incentive Payment System, 2023.
✓
Board certification likely (heuristic, not verified)
Sunil Natrajan, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + MIPS quality reporting + 2 hospital affiliations - 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 Sunil Natrajan, MD?
Below national averagePrimary specialty
Critical Care Medicine (Internal Medicine) Physician
Medicare Part D claims
998 7% vs specialty avg
MIPS final score
23.9/100 59.2 pts vs avg
Specialty distribution in Arizona
How Critical Care Medicine (Internal Medicine) Physician compares to other specialties among Arizona providers
Medicare quality performance, MIPS
Sunil Natrajan, MD's 2023 MIPS final score plotted against the Critical Care Medicine (Internal Medicine) Physician national average
- MIPS Final Score
- 23.9/100
- vs 83.1 national avg · 2023 performance year
MIPS final score (Critical Care Medicine (Internal Medicine) Physician) - 23.9/100 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).
Sunil Natrajan, MD appears in the CMS NPPES registry as a Critical Care Medicine (Internal Medicine) Physician provider holding MD credentials at 9420 E GOLF LINKS ROAD, STE 108, Tucson, AZ, 85730, with a listed phone of (520) 447-7413. NPI 1831181189 was issued on 08/22/2005.
Medicare Part D records for calendar year 2023 show 998 prescription claims written by this provider, covering 200 Medicare beneficiaries and totaling roughly $671K in drug spend, split 56% brand-name and 0% generic by claim count. On the CMS Merit-based Incentive Payment System, this provider earned a Final Score of 23.9/100 for the 2023 performance year (Quality 0, Cost 79.6), compared with the national average of 83.1.
Critical Care Medicine (Internal Medicine) Physician is a mid-sized specialty nationwide, with 6,631 enrolled providers across 53 states and an average of 1,069 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 | 1831181189 |
|---|---|
| Specialty | Critical Care Medicine (Internal Medicine) Physician |
| Credentials | MD |
| Gender | Male |
| NPI Issued | 08/22/2005 |
CMS Quality Score (MIPS)
Merit-based Incentive Payment System (MIPS) scores from CMS, 2023 performance year.
23.8844
Final Score
Avg: 83.1
0
Quality
79.6148
Cost
Reporting: Individual
Hospital and facility affiliations
Facilities where Sunil Natrajan, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" - a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.
Natrajan Enterprises PLLC
Tucson, AZ
Nuvoair Medical PC
Tucson, AZ
Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).
Brand vs generic prescribing mix · Brand-heavy
Sunil Natrajan, MD - brand share 56.0%
Critical Care Medicine (Internal Medicine) Physician average
56% brand-name claims vs 0% generic, on 998 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.
998
Total Claims
$671K
Total Drug Cost
200
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,431
- Total Day Supply
- 38,653
- Brand vs Generic
- 56% brand / 0% generic
- Brand Drug Cost
- $642K
- Antibiotic Claims
- 90
Patient Demographics
- Average Patient Age
- 76.8 years
- Avg HCC Risk Score
- 1.90
- Gender Split
- 64% female / 36% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Sunil Natrajan, MD prescribes most
Top Medicare Part D drugs by claim count, 2023
- Trelegy Ellipta
Trelegy Ellipta
180 claims
- Albuterol Sulfate …
Albuterol Sulfate Hfa
121 claims
- Breo Ellipta
Breo Ellipta
83 claims
- Montelukast Sodium
Montelukast Sodium
78 claims
- Prednisone
Prednisone
74 claims
- Azithromycin 71
Azithromycin
71 claims
- Anoro Ellipta 48
Anoro Ellipta
48 claims
- Budesonide 26
Budesonide
26 claims
| Drug | Claims |
|---|---|
| Trelegy Ellipta Fluticasone/Umeclidin/Vilanter | 180 |
| Albuterol Sulfate Hfa Albuterol Sulfate | 121 |
| Breo Ellipta Fluticasone/Vilanterol | 83 |
| Montelukast Sodium | 78 |
| Prednisone | 74 |
| Azithromycin | 71 |
| Anoro Ellipta Umeclidinium Brm/Vilanterol Tr | 48 |
| Budesonide | 26 |
| Dupixent Syringe Dupilumab | 26 |
| Stiolto Respimat Tiotropium Br/Olodaterol Hcl | 18 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
More Critical Care Medicine (Internal Medicine) Physician in AZ →
All providers in Arizona →
Compare specialties →
Critical Care Medicine (Internal Medicine) Physician Overview
How Sunil Natrajan, MD fits within the Critical Care Medicine (Internal Medicine) Physician landscape nationally.
6,631
Critical Care Medicine (Internal Medicine) Physician Providers in US
53
States with Critical Care Medicine (Internal Medicine) Physician
1,069
Avg Claims per Provider
Sunil Natrajan, MD's 998 claims are below the specialty average of 1,069.
Nearby Critical Care Medicine (Internal Medicine) Physician Providers in Arizona
Other clinicians with the same primary specialty enrolled in Arizona, drawn from the same CMS NPPES roster as Natrajan.
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 Arizona medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Critical Care Medicine (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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Frequently Asked Questions
What is Sunil Natrajan, MD's specialty? ▼
Sunil Natrajan, MD specializes in Critical Care Medicine (Internal Medicine) Physician and practices in Tucson, Arizona. Credentials: MD.
How much does Sunil Natrajan, MD prescribe under Medicare Part D? ▼
In 2023, Sunil Natrajan, MD wrote 998 Medicare Part D claims totaling $671K in drug costs for 200 beneficiaries.
What is Sunil Natrajan, MD's Medicare quality score? ▼
Sunil Natrajan, MD has a CMS MIPS Final Score of 23.9/100 (Quality: 0, Cost: 79.6). The national average MIPS Final Score is 83.1. Source: CMS Merit-based Incentive Payment System (MIPS) 2023.
Where is Sunil Natrajan, MD located? ▼
Sunil Natrajan, MD is located at 9420 E GOLF LINKS ROAD, STE 108, Tucson, AZ, 85730. Phone: (520) 447-7413.
What is Sunil Natrajan, MD's NPI number? ▼
Sunil Natrajan, MD's National Provider Identifier (NPI) is 1831181189, issued on 08/22/2005.
Does Sunil Natrajan, MD prescribe more brand-name or generic drugs? ▼
Sunil Natrajan, MD's prescribing is 56% brand-name and 0% generic drugs by claim count, with $642K in brand drug costs.
How many Critical Care Medicine (Internal Medicine) Physician providers are there in the US? ▼
There are 6,631 Critical Care Medicine (Internal Medicine) Physician providers across 53 states in the US. The average Critical Care Medicine (Internal Medicine) Physician provider writes 1,069 Medicare Part D claims per year.
What drugs does Sunil Natrajan, MD prescribe most often? ▼
Based on 2023 Medicare Part D data, Sunil Natrajan, MD's most frequently prescribed drugs include Trelegy Ellipta, Albuterol Sulfate Hfa, Breo Ellipta. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Sunil Natrajan, MD accept Medicare? ▼
Sunil Natrajan, MD appears in CMS Medicare data with 998 Part D claims and 200 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Sunil Natrajan, MD's credentials? ▼
Sunil Natrajan, MD's NPI is 1831181189 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
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.