2026 NPPES data Gastroenterology Physician NPI 1558300822 MD
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Michael Allan, MD

Gastroenterology Physician in Madison, 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 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
1K
Medicare Part D claims · 547 beneficiaries · Gastroenterology Physician avg: 833
Generic prescribing
81%
generic claims · 18% brand-name · higher generic rates reduce patient out-of-pocket costs
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Michael Allan, MD filed 1,300 Medicare Part D claims in 2023 as a Gastroenterology Physician in Madison, Wisconsin, prescribing 81% generic.

1K
Part D claims, 2023
81%
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.

Michael Allan, MD's Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023, across all CMS prescribers nationally

1,300 Top 21% higher than 79% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). This entry sits in this band. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2K+: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

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 certification likely (heuristic, not verified)

Michael Allan, MD 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 Michael Allan, MD?

Quality data not reported

NPI registry status

Active

Issued 06/05/2006

NPI 1558300822

Primary specialty

Gastroenterology Physician

Mid-sized

16,567 US NPIs in this specialty

Medicare Part D claims

1,300 56% vs specialty avg

2023 prescription claims

Specialty avg: 833

Specialty distribution in Wisconsin

How Gastroenterology Physician compares to other specialties among Wisconsin providers

Wisconsin providers

Largest specialties in Wisconsin (% of in-state providers)

Physical Therapist - 5.6%Physical Therapist5.6%Pharmacist - 4.8%Pharmacist4.8%Registered Nurse - 4.5%Registered Nurse4.5%Professional Counselor - 3.3%Professional Counselor3.3%Student in an Organized Health Care Education/Training Program - 3.3%Student in an Organized Health Care Education/Training Program3.3%Family Medicine Physician - 3.2%Family Medicine Physician3.2%Gastroenterology Physician - 0.2%Gastroenterology Physician0.2%
Largest specialties in Wisconsin (% of in-state 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 Gastroenterology Physician. Verify directly:

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).

Michael Allan, MD appears in the CMS NPPES registry as a Gastroenterology Physician provider holding MD credentials at 700 S PARK ST, Madison, WI, 53715, with a listed phone of (608) 260-2900. NPI 1558300822 was issued on 06/05/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Allan most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 1,300 prescription claims written by this provider, covering 547 Medicare beneficiaries and totaling roughly $1.1 million in drug spend, split 18% brand-name and 81% generic by claim count. These figures capture only Medicare Part D, commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

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

700 S PARK ST
Madison, WI 53715

Provider Details

NPI 1558300822
Specialty Gastroenterology Physician
Credentials MD
Gender Male
NPI Issued 06/05/2006

Hospital and facility affiliations

Facilities where Michael Allan, 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.

Dean Health Systems Inc
Madison, WI

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

Michael Allan, MD - brand share 18.0%
Gastroenterology Physician average

18% brand-name claims vs 81% generic, on 1,300 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.

1,300
Total Claims
$1.1M
Total Drug Cost
547
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,997
Total Day Supply
45,086
Brand vs Generic
18% brand / 81% generic
Brand Drug Cost
$1.0M
Generic Drug Cost
$75K
Antibiotic Claims
62

Patient Demographics

Average Patient Age
71.8 years
Avg HCC Risk Score
0.97
Gender Split
53% female / 47% male
Age Distribution
<65: 37, 65-74: 323, 75-84: 172, 85+: 15

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What Michael Allan, MD prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Omeprazole
89
Azathioprine
51
Peg 3350-Electrolyte
Sodium Chloride/Nahco3/Kcl/Peg
45
Colestipol Hcl
41
Pantoprazole Sodium
41
Xifaxan
Rifaximin
28
Humira(Cf) Pen
Adalimumab
26
Loperamide
Loperamide Hcl
25
Spironolactone
25
Alosetron Hcl
24

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Gastroenterology Physician Overview

How Michael Allan, MD fits within the Gastroenterology Physician landscape nationally.

16,567
Gastroenterology Physician Providers in US
54
States with Gastroenterology Physician
833
Avg Claims per Provider

Michael Allan, MD's 1,300 claims are above the specialty average of 833.

Nearby Gastroenterology Physician Providers in Wisconsin

Other clinicians with the same primary specialty enrolled in Wisconsin, drawn from the same CMS NPPES roster as Allan.

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 Wisconsin 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.

Frequently Asked Questions

What is Michael Allan, MD's specialty?
Michael Allan, MD specializes in Gastroenterology Physician and practices in Madison, Wisconsin. Credentials: MD.
How much does Michael Allan, MD prescribe under Medicare Part D?
In 2023, Michael Allan, MD wrote 1,300 Medicare Part D claims totaling $1.1M in drug costs for 547 beneficiaries.
Where is Michael Allan, MD located?
Michael Allan, MD is located at 700 S PARK ST, Madison, WI, 53715. Phone: (608) 260-2900.
What is Michael Allan, MD's NPI number?
Michael Allan, MD's National Provider Identifier (NPI) is 1558300822, issued on 06/05/2006.
Does Michael Allan, MD prescribe more brand-name or generic drugs?
Michael Allan, MD's prescribing is 18% brand-name and 81% generic drugs by claim count, with $1.0M 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 Michael Allan, MD prescribe most often?
Based on 2023 Medicare Part D data, Michael Allan, MD's most frequently prescribed drugs include Omeprazole, Azathioprine, Peg 3350-Electrolyte. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Michael Allan, MD accept Medicare?
Michael Allan, MD appears in CMS Medicare data with 1,300 Part D claims and 547 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Michael Allan, MD's credentials?
Michael Allan, MD's NPI is 1558300822 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

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.