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STEPHEN O'BRIEN M.D.
NPI 1699794453
Internal Medicine in Oakland, CA

Active since July 19, 2006
3100 SUMMITT STREET, 2ND FLOOR, OAKLAND, CA 94609(510) 869-8400 Get Directions Write a Review

NPPES record last updated: July 8, 2007. Verified against the NPPES registry weekly; last sync: July 26, 2026.

About Stephen O'brien M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

STEPHEN O'BRIEN M.D. (NPI 1699794453) is an individual internal medicine provider in Oakland, California, licensed in California (G74654) and active in the NPI registry since July 2006.

NPPES Registry Identity

NPI1699794453
Entity TypeIndividualMale
Primary Taxonomy207R00000X
Provider Legal NameSTEPHEN O'BRIENCredential: M.D.
Location Address3100 SUMMITT STREET, 2ND FLOOROakland, CA 94609-0000
Mailing AddressPo Box 255348Sacramento, CA 95865-5348 · (916) 854-6975 · Fax (916) 854-6864
Phone(510) 869-8400
Sole ProprietorNo
Enumeration DateJuly 19, 2006
Last NPPES UpdateJuly 8, 2007
✔ NPI 1699794453 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in CA · G74654
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
3100 SUMMITT STREET, Oakland, CA 94609
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Other Identifiers 4

Other00G746540CA · Blue Shield
Medicare UPINF67082CA
Medicare ID-Type Unspecified00G746541CA
Medicaid00G746570CA

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Stephen O'brien's NPI number?

The NPI number for Stephen O'brien is 1699794453. It was assigned to this individual provider in the NPPES registry on July 19, 2006.

Where is Stephen O'brien located?

Stephen O'brien practices at 3100 Summitt Street 2nd Floor, Oakland, CA 94609. The listed phone number is (510) 869-8400.

What is Stephen O'brien's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

When was this NPI record last updated?

The NPPES record for Stephen O'brien was last updated on July 8, 2007. NPI Profile syncs with the weekly NPPES data releases published by CMS.