NPI registry status
Active
2026 NPPES data Internal Medicine Physician NPI 1457361172 M.D., M.P.H.
Verify on CMS → Nathan Ayer, M.D., M.P.H.
Internal Medicine Physician in Loveland, Colorado.
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
10K
Medicare Part D claims · 771 beneficiaries · Internal Medicine Physician avg: 3K
Generic prescribing
89%
generic claims · 11% brand-name · higher generic rates reduce patient out-of-pocket costs
Source: CMS Medicare Part D Prescriber Public Use File, 2023
What the federal data shows
Nathan Ayer, M.D., M.P.H. filed 9,678 Medicare Part D claims in 2023 as an Internal Medicine Physician in Loveland, Colorado, prescribing 89% generic.
- 10K
- Part D claims, 2023
- 89%
- generic prescribing
- Likely
- board-certified (heuristic)
- ≥98th
- pct by Part D claim volume (lower-bound band)
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.
Federal trust snapshot
What official records show about Nathan Ayer, M.D., M.P.H.
Federal records show an active NPI with Medicare Part D prescribing activity — verifiable registry data, not a proprietary rating.
- Verified
NPI registry status
Active listing in the CMS National Provider Identifier Registry (NPI 1457361172), first enumerated 08/08/2006.
Source: CMS NPPES
- Reported
Medicare Part D participation
Filed 9,678 Medicare Part D prescription claims in the 2023 CMS public use file — indicates active Medicare prescribing participation.
Source: CMS Part D Prescriber PUF
- Reported
Board certification signal
Heuristic suggests board-certified status based on ABMS-eligible specialty taxonomy plus active CMS participation signals — not a direct ABMS verification.
- Reported
Hospital affiliations
1 CMS Care Compare hospital affiliation on record — practice footprint from the Doctors and Clinicians file.
Source: CMS Care Compare
- Not in federal data
Individual sanction lookup
PlainDoctor does not publish per-provider disciplinary determinations. Confirm current license and any individual actions through the state medical board or FSMB verification service.
Source: State medical board / FSMB
This trust snapshot summarizes only what appears in federal CMS/NPPES public records. It is not a composite score, star rating, patient review, or clinical recommendation. PlainDoctor never fabricates reviews or AggregateRating schema.
CMS NPPES provider registry desk
NPI 1457361172 · Internal Medicine Physician
NPI-10 · ENUM-LEGACY · TAX-MEGA · RX-MID · BOOK-LIGHT · PHOTO-ENUM
- NPI-10 1457361172
- ENUM-LEGACY 2006
- TAX-MEGA 173K Internal Medicine
- RX-MID 9,678
- BOOK-LIGHT 2,688 in Colorado
- PHOTO-ENUM Biykem Bozkurt · 2006
Nathan Ayer, M.D., M.P.H.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
9,678 ≥ 98th percentile 98% of 1,370,886 prescribers are in lower value bands
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.
The percentile is a conservative 100-claim band: it counts only prescribers in lower claim-volume bands. Medicare Part D claim volume is activity context, not a quality measure or recommendation. See methodology § corpus placement.
Source CMS Medicare Part D Prescriber Public Use File · 2023
✓
Board certification likely (heuristic, not verified)
Nathan Ayer, M.D., M.P.H. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation - 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 Nathan Ayer, M.D., M.P.H.?
Quality data not reportedPrimary specialty
Internal Medicine Physician
Medicare Part D claims
9,678 256% vs specialty avg
Specialty distribution in Colorado
How Internal Medicine Physician compares to other specialties among Colorado 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 Internal Medicine Physician. 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).
Practice Address
Provider Details
| NPI | 1457361172 |
|---|---|
| Specialty | Internal Medicine Physician |
| Credentials | M.D., M.P.H. |
| Gender | Male |
| NPI Issued | 08/08/2006 |
Hospital and facility affiliations
Facilities where Nathan Ayer, M.D., M.P.H. 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.
Poudre Valley Medical Group LLC
Firestone, CO
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 · Typical
Nathan Ayer, M.D., M.P.H. - brand share 11.0%
Internal Medicine Physician average
11% brand-name claims vs 89% generic, on 9,678 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.
9,678
Total Claims
$990K
Total Drug Cost
771
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 24,189
- Total Day Supply
- 712,570
- Brand vs Generic
- 11% brand / 89% generic
- Brand Drug Cost
- $817K
- Generic Drug Cost
- $169K
- Opioid Claims
- 269 (2.8% rate)
- Antibiotic Claims
- 135
Patient Demographics
- Average Patient Age
- 75.0 years
- Avg HCC Risk Score
- 1.15
- Gender Split
- 47% female / 53% male
- Age Distribution
- <65: 39, 65-74: 343, 75-84: 285, 85+: 104
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Nathan Ayer, M.D., M.P.H. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Atorvastatin Calcium
Atorvastatin Calcium
674 claims
- Levothyroxine Sodium
Levothyroxine Sodium
587 claims
- Lisinopril
Lisinopril
385 claims
- Losartan Potassium
Losartan Potassium
377 claims
- Amlodipine Besylate
Amlodipine Besylate
356 claims
- Rosuvastatin Calcium
Rosuvastatin Calcium
356 claims
- Omeprazole
Omeprazole
338 claims
- Gabapentin
Gabapentin
271 claims
| Drug | Claims |
|---|---|
| Atorvastatin Calcium | 674 |
| Levothyroxine Sodium | 587 |
| Lisinopril | 385 |
| Losartan Potassium | 377 |
| Amlodipine Besylate | 356 |
| Rosuvastatin Calcium | 356 |
| Omeprazole | 338 |
| Gabapentin | 271 |
| Tamsulosin Hcl | 269 |
| Hydrochlorothiazide | 258 |
* 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 Nathan Ayer, M.D., M.P.H. 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
Nathan Ayer, M.D., M.P.H.'s 9,678 claims are above the specialty average of 2,716.
Nationwide Internal Medicine Physician peers with similar MIPS or enrollment year
Two federal-record peer sets for Ayer, both outside Colorado so the neighborhoods are not geographic containment.
Same NPPES enumeration year (2006)
Same-specialty clinicians who entered the NPI registry in the same calendar year, outside this state.
Nearby Internal Medicine Physician Providers in Colorado
Other clinicians with the same primary specialty enrolled in Colorado, drawn from the same CMS NPPES roster as Ayer.
One of 2,688 Internal Medicine Physician providers enrolled in Colorado, 5 are shown here.
Dr. Emily Aaron
MD
Denver, CO
Dr. Cynthia Abacan
MD
Pueblo, CO
Dr. David Abbey
MS MD
Fort Collins, CO
Dr. Ahmed Abdulrahman
MD
Pueblo, CO
Dr. Victor Abela
D.O.
Denver, CO
Compare Internal Medicine Physician nationally: see state-by-state distribution →
Frequently Asked Questions
What is Nathan Ayer, M.D., M.P.H.'s specialty? ▼
Nathan Ayer, M.D., M.P.H. specializes in Internal Medicine Physician and practices in Loveland, Colorado. Credentials: M.D., M.P.H..
How much does Nathan Ayer, M.D., M.P.H. prescribe under Medicare Part D? ▼
In 2023, Nathan Ayer, M.D., M.P.H. wrote 9,678 Medicare Part D claims totaling $990K in drug costs for 771 beneficiaries.
Where is Nathan Ayer, M.D., M.P.H. located? ▼
Nathan Ayer, M.D., M.P.H. is located at 2500 ROCKY MOUNTAIN AVE, Loveland, CO, 80538. Phone: (970) 203-7050.
What is Nathan Ayer, M.D., M.P.H.'s NPI number? ▼
Nathan Ayer, M.D., M.P.H.'s National Provider Identifier (NPI) is 1457361172, issued on 08/08/2006.
Does Nathan Ayer, M.D., M.P.H. prescribe more brand-name or generic drugs? ▼
Nathan Ayer, M.D., M.P.H.'s prescribing is 11% brand-name and 89% generic drugs by claim count, with $817K in brand drug costs.
Does Nathan Ayer, M.D., M.P.H. prescribe opioids? ▼
Yes, Nathan Ayer, M.D., M.P.H. had 269 opioid claims in 2023 with an opioid prescribing rate of 2.8%.
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 Nathan Ayer, M.D., M.P.H. prescribe most often? ▼
Based on 2023 Medicare Part D data, Nathan Ayer, M.D., M.P.H.'s most frequently prescribed drugs include Atorvastatin Calcium, Levothyroxine Sodium, Lisinopril. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Nathan Ayer, M.D., M.P.H. accept Medicare? ▼
Nathan Ayer, M.D., M.P.H. appears in CMS Medicare data with 9,678 Part D claims and 771 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Nathan Ayer, M.D., M.P.H.'s credentials? ▼
Nathan Ayer, M.D., M.P.H.'s NPI is 1457361172 with credentials M.D., M.P.H.. 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
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.