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Dr. Douglas Logan Williamson, DNP

Psychiatric/Mental Health Registered Nurse in San Luis Obispo, CA · enumerated 2020.

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

National Provider Identifier

1386240844

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Registry record

Entity type Individual (Type 1)
Name Dr. Douglas Logan Williamson
Credential DNP
Sex Male
Practice address 1304 Ella St Ste B, San Luis Obispo, CA, 93401
Phone (805) 541-6000
Fax (805) 541-6001
Enumeration date Dec 9, 2020
Last updated in NPPES Mar 20, 2025

Taxonomy & licenses

163WP0808X Psychiatric/Mental Health Registered Nurse Nursing Service Providers · License NP95016180 (CA) Primary
DNP · Doctor of Nursing Practice: A clinical doctorate for advanced practice nurses. About the DNP 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

How do I verify Douglas Williamson's NPI record?
Cross-check NPI 1386240844 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1386240844 active?
Yes, as of the latest NPPES snapshot, NPI 1386240844 is active (record last updated 2025-03-20).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2025-03-20.