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Ruth A Larson, M.D.

Specialist in Poway, CA · enumerated 2005.

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

National Provider Identifier

1538167911

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Registry record

Entity type Individual (Type 1)
Name Ruth A Larson
Credential M.D.
Sex Female
Practice address 15525 Pomerado Rd, Suite A2, Poway, CA, 92064
Phone (858) 451-3311
Fax (858) 451-1142
Enumeration date Jul 11, 2005
Last updated in NPPES Nov 19, 2020

Taxonomy & licenses

207ND0101X MOHS-Micrographic Surgery Physician Allopathic & Osteopathic Physicians · License G41388 (CA) Secondary
174400000X Specialist Other Service Providers · License G41388 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
00G413880 Medicaid CA -

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

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Ruth Larson?
Ruth Larson is registered in NPPES with the primary taxonomy of Specialist. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2020-11-19.