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

John T Brennan, MD

Individual provider Emergency Medicine Physician · NPI 1891776977

John T Brennan, MD is an Emergency Medicine Physician in Onalaska, Wisconsin. Works from 4 locations. Licensed in Minnesota and Wisconsin.

Licensed in
MN, WI
In the registry since
2005
Specialties on file
4
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

191 Theater Rd
Onalaska, WI 54650
Phone: (608) 785-0940
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (3)

  • 800 West Ave S, La Crosse, WI 54601-8806 — (608) 785-0940
  • 325 Butts Ave, Tomah, WI 54660-1412 — (608) 785-0940
  • 325 Butts Ave, Tomah, WI 54660-1412 — (608) 785-0940

Specialties & licences

Family Medicine Physician (primary) Taxonomy 207Q00000X · Licence 16368 (WI)
Emergency Medicine Physician Taxonomy 207P00000X · Licence 16368 (WI)
Emergency Medicine Physician Taxonomy 207P00000X · Licence 21682 (MN)
Internal Medicine Physician Taxonomy 207R00000X · Licence 16368 (WI)

Record details

NPI number1891776977
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedNovember 7, 2005
Last updated in NPPESJune 13, 2019

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