Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Mark Demeo, MD

Individual provider Gastroenterology Physician · NPI 1972549327

Mark Demeo, MD practises Gastroenterology in Chicago, Illinois. Graduated from Rutgers New Jersey Medical School in 1983, 43 years ago. Practices with Rush University Medical Group, a 1,499-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Illinois.

Years since qualifying
43
Trained at
Rutgers New Jersey Medical School
Licensed in
IL
In the registry since
2006
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

1725 W Harrison St Ste 207
Chicago, IL 60612-3841 Not confirmed with CMS for 19 years — call before visiting
Phone: (312) 942-5861
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X (IL)

Record details

NPI number1972549327
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJune 22, 2006
Last updated in NPPESJuly 8, 2007

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyGASTROENTEROLOGY
Medical schoolRUTGERS NEW JERSEY MEDICAL SCHOOL
Graduated 1983 (43 years in practice)
Group practice Rush University Medical Group — 1499 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations4 on file with Medicare

Procedures

From CMS Care Compare, which counts the procedures a clinician billed to Original Medicare and Medicare Advantage over a recent 12-month period. CMS reports a fixed list of common procedures, so this is not everything the clinician does. Counts of 10 or fewer are given as a range, because CMS withholds small numbers.

Colonoscopy 71 times · 71st percentile
Upper gastrointestinal (GI) endoscopy for acid reflux 22 times · 52nd percentile

The percentile compares how often this clinician performed the procedure with other clinicians who performed it, as CMS calculates it. It measures volume, not outcomes or skill.

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients417
Services billed 603 a service is one billed item, such as a visit, a test or a procedure
Average patient age71

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Rush University Medical Group

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 1499 clinicians in the practice; 12 are shown here.

Other providers in Chicago