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Internal Medicine - Gastroenterology Specialists in Madison, WI

Browse 63 Internal Medicine - Gastroenterology providers listed in NPPES with a practice address in Madison, Wisconsin.

63 Healthcare Providers

How Madison compares with the U.S.

Madison has 23 clinicians in Internal Medicine - Gastroenterology per 100,000 residents, 3.7 times the U.S. rate of 6.2.

That is 63 active clinicians in Internal Medicine - Gastroenterology with a practice address in Madison, for a population of 278,001.

The Wisconsin rate is 5.7 per 100,000 residents.

What these numbers mean

Clinicians per 100,000 residents compares places of different sizes. We count active clinicians who list a practice address in the area in the federal NPI registry (NPPES) and divide by the number of people who live there, according to the U.S. Census Bureau. The U.S. rate is the same calculation for the whole country.

A higher number does not mean it is easier to get an appointment, that wait times are shorter, or that care is better. It also does not show how many clinicians are accepting new patients or which insurance plans they take. A lower number does not by itself mean there is a shortage.

City counts use the city name in each clinician's practice address. That postal city can cover a larger or smaller area than the city limits the Census Bureau uses for population, and many clinicians list only one address even if they work in several places. Cities with hospitals or large medical centers often list more specialists than the number of residents alone would suggest, because patients also come from nearby areas.

95% of clinicians in Internal Medicine - Gastroenterology in Madison listed in the CMS Medicare file (42 of 44) accept Medicare assignment. That is higher than the Wisconsin share of 90%.

What is Medicare assignment?

A clinician who accepts Medicare assignment agrees to take the Medicare-approved amount as full payment for services that Original Medicare covers. You usually still pay your deductible and coinsurance. This comes from the CMS Doctors and Clinicians file and applies to Original Medicare only. Medicare Advantage plans have their own provider networks. It does not show whether a clinician is taking new patients.

Some clinicians are listed as "may accept assignment," which means they can decide case by case. Clinicians without an assignment flag, or who are not in the CMS file, are not counted as accepting assignment. That does not mean they refuse Medicare. Ask the office before your visit.

75% of clinicians in Internal Medicine - Gastroenterology in Madison listed in the CMS Medicare file (33 of 44) have a CMS telehealth indicator, meaning their recent Medicare claims include telehealth services. That is higher than the Wisconsin share of 34%.

About the telehealth indicator

The telehealth indicator comes from CMS. It marks clinicians whose recent paid Medicare claims include services delivered by telehealth. It means a clinician has provided some services by telehealth, not that every visit can be done online. A clinician without the indicator may still offer telehealth, for example to patients who are not on Medicare. Ask the office which visits can be done by video or phone.

These figures summarize public federal data. They do not measure quality of care, appointment availability, or whether a clinician accepts your insurance or new patients. Registry addresses can be out of date. Please confirm details directly with the office and your plan. This information is not medical advice.

Prepared by T-MedInfo from NPPES, CMS and U.S. Census Bureau data. Questions or corrections: support@true-medinfo.com ยท Methodology

Sources: Clinician counts and practice addresses: NPPES NPI Registry, Centers for Medicare & Medicaid Services (CMS), data as of August 2026. Medicare assignment and telehealth indicators: CMS Doctors and Clinicians National Downloadable File. Population: U.S. Census Bureau, American Community Survey 2020-2024 5-Year Estimates, Table B01003 (Total Population).

Internal Medicine - Gastroenterology Medicare (PECOS) Enrollment & Ordering Eligibility

Medicare enrollment and order/referring eligibility listed by CMS for Internal Medicine - Gastroenterology practitioners in Madison, WI

Source: CMS PECOS
PECOS Enrolled Specialists 52 In Madison, WI
Part B Lab & Imaging Eligible 53 Diagnostic Referrals
DME Ordering Eligible 56 Durable Medical Equipment
Home Health Agency Referrals 53 HHA Ordering Eligible
Showing 1โ€“20 of 63 providers
With recent CMS data first, then Aโ€“Z

Dr. Jihad Aljabban , MD, MMSC

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment
600 Highland Ave, Madison, WI 537920001
Phone: 6082636400
NPI Identifier 1699304808
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Dr. Michael L Allan , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
700 S Park St, Madison, WI 537151830
Phone: 6082602900
NPI Identifier 1558300822
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Dr. Kerstin Eide Austin , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
Uw Hospital And Clinics, 600 Highland Ave, H4/831, Madison, WI 537920001
Phone: 6082635660
NPI Identifier 1497013023
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Dr. Katelyn Marie Backhaus , MD

Internal Medicine - Gastroenterology

Active NPI Status
600 Highland Ave, Madison, WI 537924600
Phone: 6082636400
NPI Identifier 1902486483
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Dr. Mark E. Benson , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
600 Highland Ave., Madison, WI 537923284
Phone: 6082638094
NPI Identifier 1114950987
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Dr. Antonio Bosch , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
750 University Row, Madison, WI 537051311
Phone: 6088905000
NPI Identifier 1295743656
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Dr. Siobhan M. Byrne , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
20 S Park St, Madison, WI 537151348
Phone: 6082872680
NPI Identifier 1417915836
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Dr. Freddy Caldera , DO

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
1685 Highland Avenue, 4256 Mfcb, Madison, WI 53705
Phone: 6082631995
NPI Identifier 1255594537
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Dr. Matthew Winston Caldis , MD, MS

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment
750 University Row, Madison, WI 537051311
Phone: 6088905090
NPI Identifier 1922461029
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Dr. Rodrigo A Castillo , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
750 University Row, Madison, WI 537051311
Phone: 6088905090
NPI Identifier 1811007305
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Dr. Geoffrey Khang Dang-Vu , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
700 S Park St Ste A, Madison, WI 537151830
Phone: 6082602900
NPI Identifier 1548648280
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Dr. Paul Michael Estrada , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
437 N Frances St, Madison, WI 537032013
Phone: 2102158676
NPI Identifier 1770929226
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Dr. Matthew William Ewy , MD, RD, CNSC

Internal Medicine - Gastroenterology

Active NPI Status
600 Highland Ave, Madison, WI 537920001
Phone: 6082630572
NPI Identifier 1487045696
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Lucas Fass

Internal Medicine - Gastroenterology

Active NPI Status
600 Highland Ave, Madison, WI 537921465
Phone: 6086283664
NPI Identifier 1427613793
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Dr. Terrence J. Frick , MD

Internal Medicine - Gastroenterology

Active NPI Status
4237 Manitou Way, Madison, WI 537113744
Phone: 6082888719
NPI Identifier 1851345367
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Dr. Eric A Gaumnitz , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
451 Junction Rd, Madison, WI 537172656
Phone: 6082638094
NPI Identifier 1356318943
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Dr. Jason E Gonzaga , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
700 S Park St, Madison, WI 537151830
Phone: 6082602900
NPI Identifier 1710026430
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Dr. Deepak V. Gopal , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
451 Junction Rd, Madison, WI 537172656
Phone: 6082638094
NPI Identifier 1518911064
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Dr. Gary R Griglione , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment
202 S Park St, Madison, WI 537151507
Phone: 6084175454
NPI Identifier 1013931203
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Dr. Ian Grimes , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment Telehealth Services Available
750 University Row, Madison, WI 537051311
Phone: 6088905000
NPI Identifier 1275737165
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Frequently Asked Questions about Internal Medicine - Gastroenterology in Madison

How do I check a Internal Medicine - Gastroenterology practitioner's license?

Each practitioner profile shows the NUCC taxonomy code and any state license number the practitioner reported to NPPES, plus a link to the Wisconsin licensing board lookup. NPPES entries are self-reported; current license status is published only by the state board.

Why is a practitioner missing from this list?

This list shows NPI records that are active in NPPES. A deactivated NPI keeps its profile with the deactivation date and practice history; find it with the site search by name or NPI number.