NPI registry status
Active
2026 NPPES data Allergy Physician NPI 1235175589 M.D.
Verify on CMS → Steven Kagen, M.D.
Allergy Physician in Appleton, Wisconsin.
This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers - including 1,019 in Allergy 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
643
Medicare Part D claims · 111 beneficiaries · Allergy Physician avg: 755
Generic prescribing
56%
generic claims · 44% brand-name · higher generic rates reduce patient out-of-pocket costs
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
Steven Kagen, M.D. filed 643 Medicare Part D claims in 2023 as a Allergy Physician in Appleton, Wisconsin, prescribing 56% generic.
- 643
- Part D claims, 2023
- 56%
- generic prescribing
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.
Steven Kagen, M.D.'s Medicare Part D volume vs every U.S. prescriber
Total Medicare Part D claims, 2023, across all CMS prescribers nationally
643 Top 31% higher than 69% 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
◑
Board-eligible specialty (heuristic, not verified)
Steven Kagen, M.D. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).
What does the federal data show about Steven Kagen, M.D.?
Quality data not reportedPrimary specialty
Allergy Physician
Medicare Part D claims
643 15% vs specialty avg
Specialty distribution in Wisconsin
How Allergy Physician compares to other specialties among Wisconsin 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 Allergy 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).
Steven Kagen, M.D. appears in the CMS NPPES registry as a Allergy Physician provider holding M.D. credentials at 100 W LAWRENCE ST, Appleton, WI, 54911, with a listed phone of (920) 739-9100. NPI 1235175589 was issued on 06/22/2006.
Medicare Part D records for calendar year 2023 show 643 prescription claims written by this provider, covering 111 Medicare beneficiaries and totaling roughly $357K in drug spend, split 44% brand-name and 56% generic by claim count.
Allergy Physician is a narrow specialty nationwide, with 1,019 enrolled providers across 49 states and an average of 755 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 | 1235175589 |
|---|---|
| Specialty | Allergy Physician |
| Credentials | M.D. |
| Gender | Male |
| NPI Issued | 06/22/2006 |
Brand vs generic prescribing mix · Above average
Steven Kagen, M.D. - brand share 44.0%
Allergy Physician average
44% brand-name claims vs 56% generic, on 643 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.
643
Total Claims
$357K
Total Drug Cost
111
Medicare Beneficiaries
Prescribing Breakdown
- 30-Day Fills
- 1,152
- Total Day Supply
- 32,868
- Brand vs Generic
- 44% brand / 56% generic
- Brand Drug Cost
- $335K
- Generic Drug Cost
- $22K
- Antibiotic Claims
- 17
Patient Demographics
- Average Patient Age
- 71.0 years
- Avg HCC Risk Score
- 0.93
- Gender Split
- 63% female / 37% male
Top Prescribed Drugs (Medicare Part D)
Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.
What Steven Kagen, M.D. prescribes most
Top Medicare Part D drugs by claim count, 2023
- Montelukast Sodium
Montelukast Sodium
58 claims
- Fluticasone-Salmet…
Fluticasone-Salmeterol
43 claims
- Fluticasone Propio…
Fluticasone Propionate
40 claims
- Albuterol Sulfate …
Albuterol Sulfate Hfa
36 claims
- Xolair
Xolair
34 claims
- Breo Ellipta
Breo Ellipta
31 claims
- Ipratropium Bromide
Ipratropium Bromide
31 claims
- Famotidine
Famotidine
24 claims
| Drug | Claims |
|---|---|
| Montelukast Sodium | 58 |
| Fluticasone-Salmeterol Fluticasone Propion/Salmeterol | 43 |
| Fluticasone Propionate | 40 |
| Albuterol Sulfate Hfa Albuterol Sulfate | 36 |
| Xolair Omalizumab | 34 |
| Breo Ellipta Fluticasone/Vilanterol | 31 |
| Ipratropium Bromide | 31 |
| Famotidine | 24 |
| Flovent Hfa Fluticasone Propionate | 24 |
| Symbicort Budesonide/Formoterol Fumarate | 23 |
* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.
Allergy Physician Overview
How Steven Kagen, M.D. fits within the Allergy Physician landscape nationally.
1,019
Allergy Physician Providers in US
49
States with Allergy Physician
755
Avg Claims per Provider
Steven Kagen, M.D.'s 643 claims are below the specialty average of 755.
Nearby Allergy Physician Providers in Wisconsin
Other clinicians with the same primary specialty enrolled in Wisconsin, drawn from the same CMS NPPES roster as Kagen.
Dr. John Basich
M.D.
Brookfield, WI
Dr. Walter Brummund
M.D.,PHD
Wauwatosa, WI
Dr. Mary Burnett
M.D.
Wauwatosa, WI
Dr. Robert Bush
MD
Madison, WI
Dr. Dorothy Cheung
M.D.
Milwaukee, WI
Compare Allergy 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 Wisconsin medical board, federal registration is not a license check. Credential verification guide
- Weigh a second option: compare this provider with a nearby Allergy 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 Steven Kagen, M.D.'s specialty? ▼
Steven Kagen, M.D. specializes in Allergy Physician and practices in Appleton, Wisconsin. Credentials: M.D..
How much does Steven Kagen, M.D. prescribe under Medicare Part D? ▼
In 2023, Steven Kagen, M.D. wrote 643 Medicare Part D claims totaling $357K in drug costs for 111 beneficiaries.
Where is Steven Kagen, M.D. located? ▼
Steven Kagen, M.D. is located at 100 W LAWRENCE ST, Appleton, WI, 54911. Phone: (920) 739-9100.
What is Steven Kagen, M.D.'s NPI number? ▼
Steven Kagen, M.D.'s National Provider Identifier (NPI) is 1235175589, issued on 06/22/2006.
Does Steven Kagen, M.D. prescribe more brand-name or generic drugs? ▼
Steven Kagen, M.D.'s prescribing is 44% brand-name and 56% generic drugs by claim count, with $335K in brand drug costs.
How many Allergy Physician providers are there in the US? ▼
There are 1,019 Allergy Physician providers across 49 states in the US. The average Allergy Physician provider writes 755 Medicare Part D claims per year.
What drugs does Steven Kagen, M.D. prescribe most often? ▼
Based on 2023 Medicare Part D data, Steven Kagen, M.D.'s most frequently prescribed drugs include Montelukast Sodium, Fluticasone-Salmeterol, Fluticasone Propionate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Steven Kagen, M.D. accept Medicare? ▼
Steven Kagen, M.D. appears in CMS Medicare data with 643 Part D claims and 111 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Steven Kagen, M.D.'s credentials? ▼
Steven Kagen, M.D.'s NPI is 1235175589 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.
- 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.