Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

DR. BRIAN JAMES O'NEILL M.D.
NPI 1366425985
Internal Medicine in Martinez, CA

Q: What is Brian O'neill's NPI number?

The NPI number for Brian O'neill is 1366425985. It was assigned to this individual provider in the NPPES registry on November 29, 2005.

Q: What is Brian O'neill's specialty?

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

Q: When was this NPI record last updated?

The NPPES record for Brian O'neill was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 42 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since November 29, 2005

150 MUIR RD, MARTINEZ, CA 94553(925) 372-2018(925) 372-2020 Get Directions Write a Review

NPPES record last updated: July 13, 2026. Verified against the NPPES registry weekly; last sync: August 16, 2026.

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About Dr. Brian James O'neill M.d. NPPES

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

DR. BRIAN JAMES O'NEILL M.D. (NPI 1366425985) is an individual internal medicine provider in Martinez, California, licensed in California (G42079) and active in the NPI registry since November 2005.

NPPES Registry Identity

NPI1366425985

Entity TypeIndividualMale

Primary Taxonomy207R00000X

Provider Legal NameDR. BRIAN JAMES O'NEILLCredential: M.D.

Location Address150 MUIR RDMartinez, CA 94553-4668

Mailing Address1556 Thurman WayFolsom, CA 95630-7307 · (916) 843-7330 · Fax (925) 372-2018

Phone(925) 372-2018

Fax(925) 372-2020

Sole ProprietorNo

Enumeration DateNovember 29, 2005

Last NPPES UpdateJuly 13, 2026

✔ NPI 1366425985 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 · G42079

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.

150 MUIR RD, Martinez, CA 94553

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Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

SAHIBA SINGH CHOWDHARY PSYD

Psychologist (Clinical)

150 MUIR RD
MARTINEZ, CA 94553

Contra Costa County (925) 372-2557

NESLIHAN JAMES-KANGAL PHD

Psychologist

150 MUIR RD
MARTINEZ, CA 94553

Contra Costa County (925) 370-4783

DR. BERNADETTE M DUGONI PHARM D

Pharmacist

150 MUIR RD
MARTINEZ, CA 94553

Contra Costa County (925) 372-2390

PAMELA ADHLAKHA

Occupational Therapist

150 MUIR RD
MARTINEZ, CA 94553

Contra Costa County (925) 370-4751

DR. ASHIQ MATHEW GEORGE M.D.

Psychiatry & Neurology (Psychiatry)

150 MUIR RD, MENTAL HEALTH CLINIC (116)
MARTINEZ, CA 94553

Contra Costa County (925) 372-2000

UMELO UGWOABA PHD, MPH

Psychologist

150 MUIR RD
MARTINEZ, CA 94553

Contra Costa County (925) 372-2558

BRENT RICHARD FERM PHD

Psychologist

150 MUIR RD, MENTAL HEALTH
MARTINEZ, CA 94553

Contra Costa County (925) 372-2105

DR. MATTHEW S. FALK MD

Nuclear Medicine

150 MUIR RD, VA NORTHERN CALIFORNIA HEALTH CARE SYSTEM
MARTINEZ, CA 94553

Contra Costa County (925) 372-2124

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 Brian O'neill's NPI number?

The NPI number for Brian O'neill is 1366425985. It was assigned to this individual provider in the NPPES registry on November 29, 2005.

Where is Brian O'neill located?

Brian O'neill practices at 150 Muir Rd, Martinez, CA 94553. The listed phone number is (925) 372-2018.

What is Brian O'neill'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 Brian O'neill was last updated on July 13, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 42 days ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.