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Diamond Gastroenterology Sc

Gastroenterology Physician in Oak Park, IL · enumerated 2014 · authorized official Ilysa Diamond, Owner.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1043624752

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Registry record

Entity type Organization (Type 2)
Legal business name Diamond Gastroenterology Sc
Practice address 1010 Lake St Ste 424, Oak Park, IL, 60301
Phone (708) 613-4417
Enumeration date Jun 20, 2014
Last updated in NPPES Aug 2, 2023

Taxonomy & classification

207RG0100X Gastroenterology Physician Allopathic & Osteopathic Physicians · License 36120184 (IL) Primary

Authorized official

Name Ilysa Diamond
Title Owner
Phone (708) 613-4417

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Where is Diamond Gastroenterology Sc located?
The practice location on file with NPPES is in Oak Park, IL.
How current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2023-08-02. Verify at npiregistry.cms.hhs.gov.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-08-02.