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Type 1 · Individual ✓ Active NPI ✓ Valid NPI checksum

Mark M. Youssef, M.D.

Emergency Medicine Physician in Victorville, CA · enumerated 2006.

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

National Provider Identifier

1235188400

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Registry record

Entity type Individual (Type 1)
Name Mark M. Youssef
Credential M.D.
Sex Male
Practice address 15248 11th St, Emergency Department, Victorville, CA, 92395
Phone (760) 245-8691
Fax (760) 843-6020
Enumeration date May 8, 2006
Last updated in NPPES Jan 8, 2009

Taxonomy & licenses

207P00000X Emergency Medicine Physician Allopathic & Osteopathic Physicians · License A49793 (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
00A497930 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

How do I verify Mark Youssef's NPI record?
Cross-check NPI 1235188400 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1235188400 active?
Yes, as of the latest NPPES snapshot, NPI 1235188400 is active (record last updated 2009-01-08).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2009-01-08.