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Dennis Zai, M.D., Inc

Gastroenterology Physician in Antioch, CA · enumerated 2006 · authorized official Dennis Zai, President.

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

National Provider Identifier

1578659561

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Registry record

Entity type Organization (Type 2)
Legal business name Dennis Zai, M.D., Inc
Practice address 3903 Lone Tree Way, Suite 205, Antioch, CA, 94509
Phone (925) 784-8710
Enumeration date Oct 5, 2006
Last updated in NPPES Feb 13, 2015

Taxonomy & classification

207RG0100X Gastroenterology Physician Allopathic & Osteopathic Physicians · License G38299 (CA) Primary

Authorized official

Name Dennis Zai
Title President
Phone (925) 754-8710

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

Who is the authorized official for Dennis Zai, M.D., Inc?
NPPES lists Dennis Zai (President) as the authorized official for this organization.
What is the NPI number for Dennis Zai, M.D., Inc?
The NPI for Dennis Zai, M.D., Inc is 1578659561, a Type 2 (organization) record in the CMS NPPES registry.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2015-02-13.