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Ronald M Castonguay MD Inc

Specialist in Fresno, CA · enumerated 2007 · authorized official Ronald Castonguay, Ceo.

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

National Provider Identifier

1770629701

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Registry record

Entity type Organization (Type 2)
Legal business name Ronald M Castonguay MD Inc
Other name <Unavail>
Practice address 7255 N Cedar Ave, Fresno, CA, 93720
Phone (559) 431-5353
Enumeration date Jan 29, 2007
Last updated in NPPES Mar 26, 2009

Taxonomy & classification

174400000X Specialist Other Service Providers · License A55167 (CA) Primary

Authorized official

Name Ronald Castonguay
Title Ceo
Phone (559) 431-5353

Other identifiers

Identifier Type State Issuer
00A551670 Medicaid CA -
200037156 Other CA RAILROAD MEDICARE
184324800 Other CA USDL

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

How current is this record?
Data comes from the CMS NPPES public dissemination file; this record was last updated in NPPES on 2009-03-26. Verify at npiregistry.cms.hhs.gov.
Where is Ronald M Castonguay MD Inc located?
The practice location on file with NPPES is in Fresno, CA.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-03-26.