Quick answers
- Does John N. Tasiopoulos accept Medicare assignment?
- Yes. Medicare's clinician data says John N. Tasiopoulos 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 John N. Tasiopoulos see?
- In 2024, CMS data shows 521 Original Medicare patients and 999 services for John N. Tasiopoulos. This counts Original Medicare only and measures volume, not quality.
- What is John N. Tasiopoulos's NPI number?
- 1346384492. 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 John N. Tasiopoulos, 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 | 521 |
|---|---|
| Services billed to Medicare | 999 |
| Different services or procedures | 20 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)380 services
- New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)178 services
- Biopsy of large bowel using a flexible endoscope (45380)147 services
- Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (43239)141 services
- Colorectal cancer screening; colonoscopy on individual at high risk (G0105)43 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 cholesterol75%
- High blood pressure74%
- Arthritis47%
- Diabetes28%
- Ischemic heart disease24%
- Anxiety21%
Hospitals where John N. Tasiopoulos works
Medicare's Facility Affiliation Data lists John N. Tasiopoulos 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.
- Advocate Condell Medical CenterLibertyville, IL · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 140202
- Advocate Good Shepherd HospitalBarrington, IL · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 140291
- Advocate Illinois Masonic Medical CenterChicago, IL · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 140182
- Northwestern Lake Forest HospitalLake Forest, IL · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 140130
Practice locations
Addresses where John N. Tasiopoulos is enrolled with Medicare (CMS data updated October 2, 2026).
- 1880 W Winchester Rd, Suite 201Libertyville, IL 60048 (630) 952‑1400
Group practices
Medicare enrollment lists John N. Tasiopoulos as a member of this group (CMS data updated October 2, 2026).
- Gi Partners of Illinois PLLC39 clinicians in the group
Specialties
- Gastroenterologyprimary
Other gastroenterologists in Libertyville
Clinicians with the same Medicare primary specialty in Libertyville, IL — not a recommendation.
Other clinicians in Gi Partners of Illinois PLLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | DO |
|---|---|
| Medical school | Midwestern University, Chicago College Of Osteopathic Med |
| Graduation year | 1991 (35 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1346384492 |
| 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