Janet K. Armstrong, M.D.
Internal Medicine Physician · Glasgow, MT
Janet K. Armstrong, M.D. is an internal medicine physician with a practice address in Glasgow, Montana, and NPI 1215949557, issued on Aug 13, 2006. Check the license (Montana 6460, as entered in NPPES) on the Montana Board of Medical Examiners; the Medicare figures below come from public CMS files.
- Name
- Janet K. Armstrong
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 6460 MT
Self-reported in NPPES; status is on the state search - Practice location
- 221 5TH Ave S, Glasgow, MT 59230
- Phone
- (406) 228-3400
- Enumerated
- Aug 13, 2006
- Record last updated
- Mar 26, 2008 (not updated in 18 years: call before relying on the address or phone)
- Medicaid ID
- 0099756 MT
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 324 in Montana → Look up another NPI →
Also registered at 221 5TH Ave S
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Gordon Bell, M.D.Family Medicine Physician1750393914
- Kristina Bengochea, LCPCMental Health Counselor1609221142
- Desiree CavanFamily Nurse Practitioner1386161966
- Anthony Colacino, M.D.Surgery Physician1114322898
- Robert Collins, MDObstetrics & Gynecology Physician1932558129
- Andrew Fahlgren, MDInternal Medicine Physician1598175754
Verify Janet K. Armstrong in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMontana Board of Medical Examiners
Search for license 6460Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
99% fewer Medicare Part D claims than the average internal medicine physician in 2024
16 Medicare Part D claims, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Janet K. Armstrong among 324 internal medicine physician records in Montana
Janet K. Armstrong, M.D. is one of 324 internal medicine physician records with a practice address in Montana. 72% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 7% of them.
- NPI issued2006 · 7% of these records are older, 44% newer
- In a Medicare fileYes · 72% of these records are
- In the CMS Doctors and Clinicians fileNo · 59% of these records are
- Record last updated2008 · 52% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Montana practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
2 internal medicine physician records list a practice address in Glasgow
They are 2 of the 78 NPPES records with a practice address in Glasgow, and 324 internal medicine physician records in Montana.
All 324 in Montana → Every provider in Glasgow → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Andrew Fahlgren, MDGlasgow, MT 592301598175754
- Jimmy Gray, MDPoplar, MT 592551437191699
- Scott Falley, MDWolf Point, MT 592011417971557
- Rajohn Karanjai, M,D.Sidney, MT 592701407929524
- Jerome Kessler, M.D.Sidney, MT 592701942551106
- Noel Nguewoun HerveSidney, MT 592701275072456
- Edward Pierce, MD PCSidney, MT 592701972681831
- Stephen Base, MDMiles City, MT 593011225050453
Common questions
What is Janet K. Armstrong, M.D.'s NPI number?
Janet K. Armstrong, M.D.'s National Provider Identifier (NPI) is 1215949557, issued on Aug 13, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Janet K. Armstrong, M.D. located?
The NPPES record lists a practice address at 221 5TH Ave S, Glasgow, MT, 59230. Phone: (406) 228-3400. Providers update this record themselves, so call before visiting.
How can I verify Janet K. Armstrong, M.D.'s license?
NPPES lists Montana license number 6460, as entered by the provider. Search the Montana Board of Medical Examiners at https://ebiz.mt.gov/POL/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Janet K. Armstrong, M.D. prescribe under Medicare Part D?
In 2024, Janet K. Armstrong, M.D. had 16 Medicare Part D claims; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.