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Dr. Darren Christopher Brennan, PSYD

Clinical Psychologist in Reston, VA · enumerated 2006.

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

National Provider Identifier

1770666000

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Registry record

Entity type Individual (Type 1)
Name Dr. Darren Christopher Brennan
Credential PSYD
Sex Male
Practice address 1801 Robert Fulton Dr Ste 230, Reston, VA, 20191
Fax (703) 476-7634
Enumeration date Oct 23, 2006
Last updated in NPPES Nov 27, 2023

Taxonomy & licenses

103TC0700X Clinical Psychologist Behavioral Health & Social Service Providers · License 0810005104 (VA) Primary
PSYD · Doctor of Psychology: A clinical doctorate in psychology focused on professional practice. About the PSYD 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 Darren Brennan?
The National Provider Identifier (NPI) for Darren Brennan is 1770666000, a Type 1 (individual) record in the CMS NPPES registry.
Where does Darren Brennan practice?
The practice location on file with NPPES is in Reston, VA. 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 2023-11-27.