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Mrs. Gillian Brennan, PA

Medical Physician Assistant in Syosset, NY · enumerated 2007 · practices at Syosset Radiology Pllc.

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

National Provider Identifier

1639210750

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Registry record

Entity type Individual (Type 1)
Name Mrs. Gillian Brennan
Credential PA
Sex Female
Practice address 221 Jericho Tpke, Syosset, NY, 11791
Phone (516) 496-2752
Enumeration date Feb 9, 2007
Last updated in NPPES Jun 24, 2014

Taxonomy & licenses

363AM0700X Medical Physician Assistant Physician Assistants & Advanced Practice Nursing Providers · License 009844 (NY) Primary
PA · Physician Assistant: A licensed clinician who practices medicine in collaboration with physicians, trained in a graduate PA program. About the PA 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

What is the NPI number for Gillian Brennan?
The National Provider Identifier (NPI) for Gillian Brennan is 1639210750, a Type 1 (individual) record in the CMS NPPES registry.
Where does Gillian Brennan practice?
The practice location on file with NPPES is in Syosset, NY. 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 2014-06-24.