Mary Catherine (katie) Rybak, MD
Internal Medicine Physician · Belleville, IL
Mary Catherine (katie) Rybak, MD is an internal medicine physician with a practice address in Belleville, Illinois, and NPI 1962665059, issued on Jul 8, 2008. Check the license (Illinois 036128107, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Mary Catherine (katie) Rybak
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 036128107 IL
Self-reported in NPPES; status is on the state search - Practice location
- 4550 Memorial Dr, Belleville, IL 62226
- Phone
- (618) 257-6200
- Enumerated
- Jul 8, 2008
- Record last updated
- Oct 4, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (618) 257-6679
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,238 in Illinois → Look up another NPI →
Also registered at 4550 Memorial Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Ifath Bashiruddin, M.D.Nephrology Physician1417060534
- Lakshmi Beeravolu, MDClinical Neurophysiology Physician1376745117
- Mark Deemer, ATH TRAthletic Trainer1437148723
- Behfar Dianati, M.D.Hospitalist Physician1558580852
- Michael Guignon, MDUrology Physician1700973674
- Dori Hunt, ANPAcute Care Nurse Practitioner1619260932
Verify Mary Catherine (katie) Rybak in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIllinois Department of Financial and Professional Regulation
Search for license 036128107Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
99% fewer Medicare Part D claims than the average internal medicine physician in 2024
46 Medicare Part D claims, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Celecoxib14 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.
Mary Catherine (katie) Rybak among 7,238 internal medicine physician records in Illinois
Mary Catherine (katie) Rybak, MD is one of 7,238 internal medicine physician records with a practice address in Illinois. 73% 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 45% of them.
- NPI issued2008 · 45% of these records are older, 51% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileNo · 50% of these records are
- Record last updated2021 · 47% 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 Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
27 internal medicine physician records list a practice address in Belleville
They are 27 of the 1,404 NPPES records with a practice address in Belleville, and 7,238 internal medicine physician records in Illinois.
All 7,238 in Illinois → Every provider in Belleville → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Charles Ampadu, MDSwansea, IL 622261962545269
- Michelle Burk, DOBelleville, IL 622261093817355
- Anne Cath, MDBelleville, IL 622261417937574
- Philip Chu, MDSwansea, IL 622261396797841
- Vibhu Dhawan, MDBelleville, IL 622261033315965
- Richard Fikes, DOBelleville, IL 622261235176686
- Kathleen Fournier, MDBelleville, IL 622261023088903
- Victoria Jansen, MDSwansea, IL 622261932191863
Common questions
What is Mary Catherine (katie) Rybak, MD's NPI number?
Mary Catherine (katie) Rybak, MD's National Provider Identifier (NPI) is 1962665059, issued on Jul 8, 2008. An NPI identifies a provider in billing; it is not a license.
Where is Mary Catherine (katie) Rybak, MD located?
The NPPES record lists a practice address at 4550 Memorial Dr, Belleville, IL, 62226. Phone: (618) 257-6200. Providers update this record themselves, so call before visiting.
How can I verify Mary Catherine (katie) Rybak, MD's license?
NPPES lists Illinois license number 036128107, as entered by the provider. Search the Illinois Department of Financial and Professional Regulation at https://idfpr.illinois.gov/checklicense.html. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Mary Catherine (katie) Rybak, MD prescribe under Medicare Part D?
In 2024, Mary Catherine (katie) Rybak, MD had 46 Medicare Part D claims; 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.