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

John J. O'Brien, MD

Individual provider Family Medicine Physician · NPI 1083689061

John J. O'Brien, MD is a Family Medicine Physician in O Fallon, Missouri. Works from 2 locations. Licensed in Missouri.

Licensed in
MO
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

2630 Highway K
O Fallon, MO 63368-6624
Phone: (636) 240-5454
Fax: (618) 980-5335
Show map & directions

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

Additional practice locations (1)

  • 9426 Phoenix Village Pkwy, O Fallon, MO 63368-4781 — (636) 561-5999

Specialties & licences

Family Medicine Physician (primary) Taxonomy 207Q00000X · Licence R3E76 (MO)

Record details

NPI number1083689061
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedFebruary 22, 2006
Last updated in NPPESFebruary 24, 2021
Certification dateFebruary 24, 2021
Mailing address2630 Highway K, O Fallon, MO 63368-6624

Other providers in O Fallon