Brett A. Linzer, M.D.
Internal Medicine Physician · Oconomowoc, WI
Brett A. Linzer, M.D. is an internal medicine physician with a practice address in Oconomowoc, Wisconsin, and NPI 1083686653, issued on Feb 7, 2006. Check the license (Wisconsin 42014, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Brett A. Linzer
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 42014 WI
Self-reported in NPPES; status is on the state search - Practice location
- 1185 Corporate Center Dr, Oconomowoc, WI 53066
- Phone
- (262) 928-8400
- Enumerated
- Feb 7, 2006
- Record last updated
- Apr 13, 2012 (not updated in 14 years: call before relying on the address or phone)
- Medicaid ID
- 32629400 WI
- Medicare enrollment
- Enrolled (PECOS I20100727000860); may accept Medicare assignment
- Medical or professional school
- Loyola University Of Chicago, Stritch School Of Medicine, 1996
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 2,078 in Wisconsin → Look up another NPI →
Also registered at 1185 Corporate Center Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Firas Ghanem, M.D.Cardiovascular Disease Physician1124008529
- John Gucciardi, M.D.Family Medicine Physician1760417430
Verify Brett A. Linzer in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 42014Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
100% more Medicare Part D claims than the average internal medicine physician in 2024
6,344 Medicare Part D claims for 521 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 182 claims were for opioids.
Most prescribed
- Losartan Potassium454 claims
- Atorvastatin Calcium359 claims
- Levothyroxine Sodium296 claims
- Lisinopril261 claims
- Amlodipine Besylate206 claims
- Metoprolol Succinate203 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.
Brett A. Linzer among 2,078 internal medicine physician records in Wisconsin
Brett A. Linzer, M.D. is one of 2,078 internal medicine physician records with a practice address in Wisconsin. 70% 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 9% of them.
- NPI issued2006 · 9% of these records are older, 46% newer
- In a Medicare fileYes · 70% of these records are
- In the CMS Doctors and Clinicians fileYes · 53% of these records are
- Graduated1996 · median 2002 among the 1,098 with a school on file
- Record last updated2012 · 55% 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 Wisconsin practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
12 internal medicine physician records list a practice address in Oconomowoc
They are 12 of the 506 NPPES records with a practice address in Oconomowoc, and 2,078 internal medicine physician records in Wisconsin.
All 2,078 in Wisconsin → Every provider in Oconomowoc → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Tulay Aksoy, MDSummit, WI 530661245485697
- Brenda Boschek, M.D.Oconomowoc, WI 530661154393833
- Julius BreyerOconomowoc, WI 530661760621809
- Dan Cleary, MDOconomowoc, WI 530661972615136
- Eric Conradson, M.D.Oconomowoc, WI 530661518976232
- William Cooper, MDOconomowoc, WI 530661023078037
- Pravin Gupta, M.D.Summit, WI 530661124132188
- John Murphy, MDOconomowoc, WI 530661235246653
Common questions
What is Brett A. Linzer, M.D.'s NPI number?
Brett A. Linzer, M.D.'s National Provider Identifier (NPI) is 1083686653, issued on Feb 7, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Brett A. Linzer, M.D. located?
The NPPES record lists a practice address at 1185 Corporate Center Dr, Oconomowoc, WI, 53066. Phone: (262) 928-8400. Providers update this record themselves, so call before visiting.
How can I verify Brett A. Linzer, M.D.'s license?
NPPES lists Wisconsin license number 42014, as entered by the provider. Search the Wisconsin Medical Examining Board at https://dsps.wi.gov/Pages/BoardsCouncils/MEB/Default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Brett A. Linzer, M.D. prescribe under Medicare Part D?
In 2024, Brett A. Linzer, M.D. had 6,344 Medicare Part D claims for 521 beneficiaries; 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.