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Dr. Johnston Co, M.D.

Preventive Medicine/Occupational Environmental Medicine Physician in Stockton, CA · enumerated 2007.

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

National Provider Identifier

1114044096

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Registry record

Entity type Individual (Type 1)
Name Dr. Johnston Co
Credential M.D.
Sex Male
Practice address 1801 E March Ln # D-480, Stockton, CA, 95210
Phone (209) 954-3200
Enumeration date Mar 23, 2007
Last updated in NPPES Jul 8, 2007

Taxonomy & licenses

2083P0500X Preventive Medicine/Occupational Environmental Medicine Physician Allopathic & Osteopathic Physicians · License G077293 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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

What is the NPI number for Johnston Co?
The National Provider Identifier (NPI) for Johnston Co is 1114044096, a Type 1 (individual) record in the CMS NPPES registry.
Where does Johnston Co practice?
The practice location on file with NPPES is in Stockton, CA. Providers can have multiple locations; NPPES lists the primary practice address.

Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2007-07-08.