Marcia L. O Brien, M.D.
Family Medicine Physician · Rochester, MN
Marcia L. O Brien, M.D. is a family medicine physician with a practice address in Rochester, Minnesota, and NPI 1558348524, issued on Dec 29, 2005. Check the license (Minnesota 43748, as entered in NPPES) on the Minnesota Board of Medical Practice; the Medicare figures below come from public CMS files.
- Name
- Marcia L. O Brien
- Credential
- M.D.
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- 43748 MN
Self-reported in NPPES; status is on the state search - Practice location
- 200 1St St SW, Rochester, MN 55905
- Phone
- (507) 284-2511
- Enumerated
- Dec 29, 2005
- Record last updated
- Aug 19, 2020 (not updated in 6 years: call before relying on the address or phone)
- Medicaid ID
- 592402200 MN
- Medicare enrollment
- Enrolled (PECOS I20100115000898); accepts Medicare assignment
- Medical or professional school
- University Of Wisconsin School Of Medicine, 2000
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 3,985 in Minnesota → Look up another NPI →
Also registered at 200 1St St SW
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Uzoamaka Abajue, PHARMDPharmacist1982335295
- Francisco Abarca Rendon, MDIndependent Medical Examiner Physician1790096246
Verify Marcia L. O Brien in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMinnesota Board of Medical Practice
Search for license 43748Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
60% fewer Medicare Part D claims than the average family medicine physician in 2024
1,414 Medicare Part D claims for 166 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. 22 claims were for opioids.
Most prescribed
- Atorvastatin Calcium93 claims
- Rosuvastatin Calcium77 claims
- Levothyroxine Sodium65 claims
- Amlodipine Besylate64 claims
- Losartan Potassium64 claims
- Metformin Hcl Er57 claims
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.
Bills Medicare through one group practice
- Mayo ClinicRochester, MN
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Marcia L. O Brien among 3,985 family medicine physician records in Minnesota
Marcia L. O Brien, M.D. is one of 3,985 family medicine physician records with a practice address in Minnesota. 74% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 88% newer
- In a Medicare fileYes · 74% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated2000 · median 2006 among the 2,483 with a school on file
- Record last updated2020 · 63% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a Minnesota practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
200 family medicine physician records list a practice address in Rochester
They are 200 of the 12,854 NPPES records with a practice address in Rochester, and 3,985 family medicine physician records in Minnesota.
All 3,985 in Minnesota → Every provider in Rochester → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- David Agerter, M.D.Rochester, MN 559051194701227
- Thomas Billings, D.O.Rochester, MN 559051497731228
- Elliot Bruhl, MDRochester, MN 559051083691612
- Elizabeth Bunch, M.D.Rochester, MN 559051902888639
- Casey Caldwell, M.D.Rochester, MN 559051356327696
- Robert Fish, M.D.Rochester, MN 559051578540282
- Walter Franz, M.D.Rochester, MN 559051265419386
- Margaret Gill, M.D.Rochester, MN 559051023095619
Common questions
What is Marcia L. O Brien, M.D.'s NPI number?
Marcia L. O Brien, M.D.'s National Provider Identifier (NPI) is 1558348524, issued on Dec 29, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Marcia L. O Brien, M.D. located?
The NPPES record lists a practice address at 200 1St St SW, Rochester, MN, 55905. Phone: (507) 284-2511. Providers update this record themselves, so call before visiting.
How can I verify Marcia L. O Brien, M.D.'s license?
NPPES lists Minnesota license number 43748, as entered by the provider. Search the Minnesota Board of Medical Practice at https://mn.gov/boards/medical-practice/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Marcia L. O Brien, M.D. prescribe under Medicare Part D?
In 2024, Marcia L. O Brien, M.D. had 1,414 Medicare Part D claims for 166 beneficiaries; the average among family medicine physician prescribers was 3,544. 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.