William R. Cooper, MD
Internal Medicine Physician · Oconomowoc, WI
William R. Cooper, MD is an internal medicine physician with a practice address in Oconomowoc, Wisconsin, and NPI 1023078037, issued on Mar 24, 2006. Check the license (Wisconsin 49183, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- William R. Cooper
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 49183 WI
Self-reported in NPPES; status is on the state search - Practice location
- 1185 Corporate Center Dr Ste 175, Oconomowoc, WI 53066
- Phone
- (262) 928-8400
- Enumerated
- Mar 24, 2006
- Record last updated
- Apr 16, 2012 (not updated in 14 years: call before relying on the address or phone)
- Medicaid ID
- 328213900 MN
- Medicare enrollment
- Enrolled (PECOS I20060817000516); accepts Medicare assignment
- Medical or professional school
- University Of Wisconsin School Of Medicine, 1993
- 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 Ste 175
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Sarah Schwigel, MSN, APNP, FNP-CFamily Nurse Practitioner1841020500
- Donna Voigt, APNPNurse Practitioner1639143662
- Chris Yiannias, D.O.Internal Medicine Physician1750356713
Verify William R. Cooper in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 49183Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
4.1 times the Medicare Part D claims of the average internal medicine physician in 2024
12,902 Medicare Part D claims for 652 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 12% of claims. 135 claims were for opioids.
Most prescribed
- Atorvastatin Calcium1,007 claims
- Losartan Potassium709 claims
- Levothyroxine Sodium527 claims
- Amlodipine Besylate487 claims
- Pantoprazole Sodium385 claims
- Eliquis368 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
- Prohealth Medical Group IncOconomowoc, WI
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William R. Cooper among 2,078 internal medicine physician records in Wisconsin
William R. Cooper, MD 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
- Graduated1993 · 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
- Pravin Gupta, M.D.Summit, WI 530661124132188
- Brett Linzer, M.D.Oconomowoc, WI 530661083686653
- John Murphy, MDOconomowoc, WI 530661235246653
Common questions
What is William R. Cooper, MD's NPI number?
William R. Cooper, MD's National Provider Identifier (NPI) is 1023078037, issued on Mar 24, 2006. An NPI identifies a provider in billing; it is not a license.
Where is William R. Cooper, MD located?
The NPPES record lists a practice address at 1185 Corporate Center Dr Ste 175, Oconomowoc, WI, 53066. Phone: (262) 928-8400. Providers update this record themselves, so call before visiting.
How can I verify William R. Cooper, MD's license?
NPPES lists Wisconsin license number 49183, 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 William R. Cooper, MD prescribe under Medicare Part D?
In 2024, William R. Cooper, MD had 12,902 Medicare Part D claims for 652 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.