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Steven Campbell Marek, M.D.

Hospitalist Physician in Oak Lawn, IL · enumerated 2011.

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

National Provider Identifier

1588953897

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Registry record

Entity type Individual (Type 1)
Name Steven Campbell Marek
Credential M.D.
Sex Male
Practice address 4440 W 95th St Ste 2177h, Oak Lawn, IL, 60453
Phone (847) 723-5577
Fax (708) 684-4716
Enumeration date Apr 7, 2011
Last updated in NPPES Jan 22, 2026

Taxonomy & licenses

208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License 0101256140 (VA) Secondary
208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License MD042379 (DC) Secondary
208M00000X Hospitalist Physician Allopathic & Osteopathic Physicians · License 036-143896 (IL) Primary
390200000X Student in an Organized Health Care Education/Training Program Student, Health Care 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.

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Frequently asked questions

Where does Steven Marek practice?
The practice location on file with NPPES is in Oak Lawn, IL. Providers can have multiple locations; NPPES lists the primary practice address.
What is the NPI number for Steven Marek?
The National Provider Identifier (NPI) for Steven Marek is 1588953897, a Type 1 (individual) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-01-22.