Ioannis Karkatzounis, MD
Hospitalist Physician · Oshkosh, WI
Ioannis Karkatzounis, MD is a hospitalist physician with a practice address in Oshkosh, Wisconsin, and NPI 1639335235, issued on Aug 3, 2008. Check the license (Wisconsin 2960, as entered in NPPES) on the Wisconsin Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Ioannis Karkatzounis
- Credential
- MD
- Primary taxonomy
- Hospitalist Physician 208M00000X
- License numbers
- 2960 WI
036-120385 IL
036120385 IL
Self-reported in NPPES; status is on the state search - Practice location
- 855 N Westhaven Dr, Oshkosh, WI 54904
- Phone
- (920) 303-8700
- Enumerated
- Aug 3, 2008
- Record last updated
- Sep 26, 2024
- Fax
- (920) 456-7601
- Medicaid ID
- 100004698 WI
- Medicare enrollment
- Enrolled (PECOS I20090813000167); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest hospitalist physician records → All 894 in Wisconsin → Look up another NPI →
Also registered at 855 N Westhaven Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Rami Abumasmah, MDHematology & Oncology Physician1972779551
- Abdulmajid AdamHospitalist Physician1528362258
- Awais Ahmed, MDGastroenterology Physician1316213481
- Kate Alexander, PA-CPhysician Assistant1700466414
- Hussein Alramini, M.D.Hospitalist Physician1497106512
- Ammar Alzoubi, MDInternal Medicine Physician1598773152
Verify Ioannis Karkatzounis in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWisconsin Medical Examining Board
Search for license 2960Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
23% fewer Medicare Part D claims than the average hospitalist physician in 2024
400 Medicare Part D claims for 188 beneficiaries, against an average of 521 among the 21,613 providers of this specialty who prescribed in Part D. 21 claims were for opioids.
Most prescribed
- Prednisone27 claims
- Amlodipine Besylate25 claims
- Atorvastatin Calcium24 claims
- Cefuroxime24 claims
- Clopidogrel22 claims
- Pantoprazole Sodium22 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.
Industry payments in 2024: $292.60
7 payments; by number, the most common kind was food and beverage; the largest payer was Harmony Biosciences LLC. The 7,324 providers of this specialty with any payment received $494.84 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through 7 group practices
- 24 ON Physicians PCCarbondale, IL
- Beloit Health System IncBeloit, WI
- Cep America-Illinois Hospitalists, LLPO Fallon, IL
- Genesis Health SystemDavenport, IA
- Osf Multi-Specialty GroupUrbana, IL
- Sound Physicians OF Illinois LLCNormal, IL
- Trinity Medical Staffing LLCMount Vernon, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Ioannis Karkatzounis among 894 hospitalist physician records in Wisconsin
Ioannis Karkatzounis, MD is one of 894 hospitalist physician records with a practice address in Wisconsin. 91% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2008, is newer than 25% of them.
- NPI issued2008 · 25% of these records are older, 70% newer
- In a Medicare fileYes · 91% of these records are
- In the CMS Doctors and Clinicians fileYes · 86% of these records are
- Graduated1999 · median 2011 among the 768 with a school on file
- Record last updated2024 · 29% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 208M00000X and a Wisconsin practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Hospitalist Physician providers in Wisconsin
There are 894 hospitalist physician records in Wisconsin.
All 894 in Wisconsin → Every provider in Oshkosh → Hospitalist Physician nationwide →
The 8 hospitalist physician records with the nearest ZIP codes
- Abdulmajid AdamOshkosh, WI 549041528362258
- Hussein Alramini, M.D.Oshkosh, WI 549041497106512
- Karl Baum, MDOshkosh, WI 549041497749402
- Ann-Marie Edwards, MDOshkosh, WI 549041619318508
- Raul Garcia, MDOshkosh, WI 549041487648499
- David Hanes, DOOshkosh, WI 549041982680286
- Angelea Heider, MDOshkosh, WI 549041477048437
- Sean Huff, DOOshkosh, WI 549041679954614
Common questions
What is Ioannis Karkatzounis, MD's NPI number?
Ioannis Karkatzounis, MD's National Provider Identifier (NPI) is 1639335235, issued on Aug 3, 2008. An NPI identifies a provider in billing; it is not a license.
Where is Ioannis Karkatzounis, MD located?
The NPPES record lists a practice address at 855 N Westhaven Dr, Oshkosh, WI, 54904. Phone: (920) 303-8700. Providers update this record themselves, so call before visiting.
How can I verify Ioannis Karkatzounis, MD's license?
NPPES lists Wisconsin license number 2960, 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 Ioannis Karkatzounis, MD prescribe under Medicare Part D?
In 2024, Ioannis Karkatzounis, MD had 400 Medicare Part D claims for 188 beneficiaries; the average among hospitalist physician prescribers was 521. 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.