Quick answers
- Does Ioannis Karkatzounis accept Medicare assignment?
- Yes. Medicare's clinician data says Ioannis Karkatzounis accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Ioannis Karkatzounis see?
- In 2024, CMS data shows 386 Original Medicare patients and 946 services for Ioannis Karkatzounis. This counts Original Medicare only and measures volume, not quality.
- What is Ioannis Karkatzounis's NPI number?
- 1639335235. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Ioannis Karkatzounis, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 386 |
|---|---|
| Services billed to Medicare | 946 |
| Different services or procedures | 9 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes (99231)357 services
- Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)291 services
- Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes (99222)121 services
- Hospital discharge day management, 30 minutes or less (99238)89 services
- Hospital discharge day management, more than 30 minutes (99239)54 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Arthritis61%
- Heart failure55%
- Ischemic heart disease54%
- Anxiety48%
Hospitals where Ioannis Karkatzounis works
Medicare's Facility Affiliation Data lists Ioannis Karkatzounis at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Deaconess Illinois CrossroadsMount Vernon, IL · Acute Care Hospital · Emergency services: listed by Medicare · CCN 140294
- Genesis Medical Center-DavenportDavenport, IA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 160033
- Herrin HospitalHerrin, IL · Acute Care Hospital · Medicare rating: 1 of 5 stars · Emergency services: listed by Medicare · CCN 140011
- Memorial Hospital of CarbondaleCarbondale, IL · Acute Care Hospital · Medicare rating: 1 of 5 stars · Emergency services: listed by Medicare · CCN 140164
- OSF Sacred Heart Medical CenterDanville, IL · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 140093
Practice locations
Addresses where Ioannis Karkatzounis is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 8; the Medicare profile lists all.
- 1105 6th StTraverse City, MI 49684 (231) 935‑5000
- 1227 E Rusholme St, Mercyone GenesisDavenport, IA 52803 (563) 421‑1000
- 1300 Franklin Ave, Suite 380Normal, IL 61761 (309) 268‑3589
- 1400 W Park StUrbana, IL 61801 (217) 337‑2000
- 405 W Jackson StCarbondale, IL 62901 (618) 549‑0721
Group practices
Medicare enrollment lists Ioannis Karkatzounis as a member of these groups (CMS data updated October 2, 2026).
- OSF Multi-Specialty Group2,114 clinicians in the group
- 24 on Physicians PC272 clinicians in the group
- Genesis Health System261 clinicians in the group
- Sound Physicians of Illinois LLC193 clinicians in the group
- Grand Traverse Physician Services PC113 clinicians in the group
- Trinity Medical Staffing LLC36 clinicians in the group
Specialties
- Internal Medicineprimary
Other internal medicine doctors in Traverse City
Clinicians with the same Medicare primary specialty in Traverse City, MI — not a recommendation.
Other clinicians in OSF Multi-Specialty Group
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1999 (27 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1639335235 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians