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Michael P O'Brien, M.D.

Diagnostic Radiology Physician in Waukesha, WI · enumerated 2006.

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

National Provider Identifier

1194777888

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Registry record

Entity type Individual (Type 1)
Name Michael P O'Brien
Credential M.D.
Sex Male
Practice address W231n1440 Corporate Ct, Waukesha, WI, 53186
Phone (262) 896-6000
Enumeration date May 17, 2006
Last updated in NPPES Dec 30, 2024

Taxonomy & licenses

2085R0202X Diagnostic Radiology Physician Allopathic & Osteopathic Physicians · License 48359 (WI) Primary
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
34967100 Medicaid WI -

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 Michael O'Brien?
The National Provider Identifier (NPI) for Michael O'Brien is 1194777888, a Type 1 (individual) record in the CMS NPPES registry.
Where does Michael O'Brien practice?
The practice location on file with NPPES is in Waukesha, WI. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2024-12-30.