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

Individual provider Neurology Physician · NPI 1811981699

Dr. Dennis Obrien, MD is a Neurology Physician in Billings, Montana. Licensed in Illinois. Registered with an NPI since 2005.

Licensed in
IL
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

801 N 29th St
Billings, MT 59101-0905
Phone: (406) 238-2500
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Neurology Physician (primary) Taxonomy 2084N0400X · Licence 36099965 (IL)

Record details

NPI number1811981699
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedSeptember 7, 2005
Last updated in NPPESDecember 11, 2014
Mailing addressPo Box 35100, Billings, MT 59107-5100

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