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John Mastrovich, M.D., P.A.

Allergy & Immunology Physician in San Antonio, TX · enumerated 2006 · authorized official John Mastrovich, President.

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

National Provider Identifier

1538264213

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Registry record

Entity type Organization (Type 2)
Legal business name John Mastrovich, M.D., P.A.
Other name <Unavail>
Practice address 20650 Stone Oak Pkwy, Suite 106, San Antonio, TX, 78258
Phone (210) 342-6200
Fax (210) 342-6201
Enumeration date Sep 14, 2006
Last updated in NPPES Oct 12, 2007

Taxonomy & classification

207K00000X Allergy & Immunology Physician Allopathic & Osteopathic Physicians · License L2449 (TX) Primary

Authorized official

Name John Mastrovich
Title President
Phone (210) 342-6200

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 John Mastrovich, M.D., P.A.?
NPPES lists John Mastrovich (President) as the authorized official for this organization.
What is the NPI number for John Mastrovich, M.D., P.A.?
The NPI for John Mastrovich, M.D., P.A. is 1538264213, 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 2007-10-12.