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Internal Medicine - Gastroenterology Specialists in Alton, IL

Browse 5 Internal Medicine - Gastroenterology providers listed in NPPES with a practice address in Alton, Illinois.

5 Healthcare Providers

How Alton compares with the U.S.

5 active clinicians in Internal Medicine - Gastroenterology list a practice address in Alton, IL in the NPI registry.

With fewer than 10 clinicians, rates per 100,000 residents are not reliable enough to compare.

Too few clinicians in Internal Medicine - Gastroenterology in Alton are listed in the CMS Medicare file to report Medicare assignment or telehealth shares.

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 Registry addresses can be out of date.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.

Showing 1โ€“5 of 5 providers
With recent CMS data first, then Aโ€“Z

Dr. Mark M Allendorph , MD

Internal Medicine - Gastroenterology

Active NPI Status
2 Memorial Dr, Suite 205, Alton, IL 620026723
Phone: 6184655849
NPI Identifier 1922094002
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Dr. Ahmad A Karadaghy , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment
4 Memorial Dr Ste 230b, Alton, IL 620026705
Phone: 6184637874
NPI Identifier 1619963063
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Dr. Khalid Naseer , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment
2 Saint Anthonys Way Ste 105, Alton, IL 620024580
Phone: 6184652761
NPI Identifier 1851341366
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Dr. David Robert Riedel , MD

Internal Medicine - Gastroenterology

Active NPI Status
4 Memorial Dr Ste 230, Alton, IL 620026704
Phone: 6184637874
NPI Identifier 1073505004
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Dr. Yixi Tu , MD

Internal Medicine - Gastroenterology

Active NPI Status Accepts Medicare Assignment
4 Memorial Dr Ste 230, Alton, IL 620026704
Phone: 6184637874
NPI Identifier 1861854929
View Full Profile

Frequently Asked Questions about Internal Medicine - Gastroenterology in Alton

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 Illinois 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.