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

Dennis M. O'Brien Jr., MD

Individual provider Pediatric Hematology & Oncology Physician · NPI 1568673903

Dennis M. O'Brien Jr., MD is a Pediatric Hematology & Oncology Physician in Indianapolis, Indiana. Works from 2 locations. Licensed in Indiana.

Licensed in
IN
In the registry since
2007
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

705 Riley Hospital Dr
Indianapolis, IN 46202-5109
Phone: (317) 944-2143
Fax: (317) 944-3107
Show map & directions

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

Additional practice locations (1)

  • 11104 Parkview Circle Dr Ste 50, Fort Wayne, IN 46845-1733 — (260) 266-5400

Specialties & licences

Pediatric Hematology & Oncology Physician (primary) Taxonomy 2080P0207X · Licence 01063696A (IN)

Record details

NPI number1568673903
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedMay 25, 2007
Last updated in NPPESMarch 6, 2026
Certification dateMarch 6, 2026

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