Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum
Ahmad Osama Rez, M.D
Hospitalist Physician in Alton, IL · enumerated 2007.
Data current as of Jul 13, 2026 · sourced from CMS NPPES
National Provider Identifier
1356537179
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Registry record
Entity type Individual (Type 1)
Name Ahmad Osama Rez
Credential M.D
Sex Male
Practice address 1 Saint Anthonys Way, Alton, IL, 62002
Phone (314) 317-0600
Fax (314) 317-0606
Enumeration date Sep 16, 2007
Last updated in NPPES Sep 19, 2025
Taxonomy & licenses
208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 2010014085 (MO) Secondary
208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 036131216 (IL) Secondary
208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 036.131216 (IL) Primary
207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 036.131216 (IL) Secondary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure.
About the MD credential
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.
Frequently asked questions
Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Ahmad Rez?
Ahmad Rez is registered in NPPES with the primary taxonomy of Hospitalist Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.
Other providers at this practice address
Browse all → Figueroa and Associates Anesthesia Group, Ltd. Specialist · Alton, IL NPI 1831198357 Stromsdorfer-Tolod Medical Lab Ltd. Clinical Medical Laboratory · Alton, IL NPI 1659354645 Isidro Tolod Anatomic Pathology & Clinical Pathology Physician · Alton, IL NPI 1063495059 John Zabrowski Diagnostic Radiology Physician · Alton, IL NPI 1821058397 Banti Mahanta Diagnostic Radiology Physician · Alton, IL NPI 1790745297 Gino Diiorio Diagnostic Radiology Physician · Alton, IL NPI 1700847761 Ronald Levy Diagnostic Radiology Physician · Alton, IL NPI 1760443741 David Huyette Diagnostic Radiology Physician · Alton, IL NPI 1295782480
Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-09-19.