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Mark E Obrien, MD

Internal Medicine Physician in Benton Harbor, MI · enumerated 2006.

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

National Provider Identifier

1841221348

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Registry record

Entity type Individual (Type 1)
Name Mark E Obrien
Credential MD
Sex Male
Practice address 800 M 139, Benton Harbor, MI, 49022
Phone (269) 927-5400
Fax (269) 927-5493
Enumeration date Jul 5, 2006
Last updated in NPPES Jan 7, 2013

Taxonomy & licenses

207R00000X Internal Medicine Physician Allopathic & Osteopathic Physicians · License 4301080677 (MI) Primary
208000000X Pediatrics Physician Allopathic & Osteopathic Physicians · License 4301080677 (MI) Secondary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
4605349 Medicaid MI -

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

What is the NPI number for Mark Obrien?
The National Provider Identifier (NPI) for Mark Obrien is 1841221348, a Type 1 (individual) record in the CMS NPPES registry.
Where does Mark Obrien practice?
The practice location on file with NPPES is in Benton Harbor, MI. Providers can have multiple locations; NPPES lists the primary practice address.

Other providers at this practice address

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2013-01-07.