Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Mr. Mark John Castellanet, MD

Individual provider Cardiovascular Disease Physician · NPI 1538165782

Mr. Mark John Castellanet, MD is a Cardiovascular Disease Physician in Los Alamitos, California. Licensed in California. Registered with an NPI since 2005.

Licensed in
CA
In the registry since
2005
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

3801 Katella Ave Ste 401
Los Alamitos, CA 90720-3375
Phone: (562) 598-3200
Fax: (562) 799-3646
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Cardiovascular Disease Physician (primary) Taxonomy 207RC0000X · Licence GZ8642 (CA)

Record details

NPI number1538165782
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJune 22, 2005
Last updated in NPPESJuly 13, 2026

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