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

Dr. John Gregory Duffy, MD

Individual provider Psychiatry Physician · NPI 1255497251

Dr. John Gregory Duffy, MD is a Psychiatry Physician in Santa Ana, California. Licensed in California. Registered with an NPI since 2006.

Licensed in
CA
In the registry since
2006
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

1401 N Tustin Ave Ste 130 Ste 165
Santa Ana, CA 92705
Phone: (714) 542-3008
Fax: (714) 542-3617
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Psychiatry Physician (primary) Taxonomy 2084P0800X · Licence A54948 (CA)

Record details

NPI number1255497251
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedDecember 28, 2006
Last updated in NPPESMarch 15, 2023
Certification dateMarch 15, 2023

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