Gregory S. Granzeier, DO
Obstetrics & Gynecology Physician · Roscoe, IL
Gregory S. Granzeier, DO is an obstetrics & gynecology physician with a practice address in Roscoe, Illinois, and NPI 1134239320, issued on Aug 30, 2006. Check the license (Illinois 036-094024, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Gregory S. Granzeier
- Credential
- DO
- Primary taxonomy
- Obstetrics & Gynecology Physician 207V00000X
- License number
- 036-094024 IL
Self-reported in NPPES; status is on the state search - Practice location
- 5000 Prairie Rose Dr, Roscoe, IL 61073
- Phone
- (815) 971-2000
- Enumerated
- Aug 30, 2006
- Record last updated
- Jan 21, 2010 (not updated in 16 years: call before relying on the address or phone)
- Medicaid ID
- 036094024 IL
- Medicare enrollment
- Enrolled (PECOS I20041012001410); accepts Medicare assignment
- Medical or professional school
- New York College Of Osteo Medicine Of New York Institute Of Technology, 1991
- Entity
- Type 1 · individual
Also registered at 5000 Prairie Rose Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Rana Abdul-Khalek, MDObstetrics & Gynecology Physician1275768087
- Elizabeth Burke, CNMAdvanced Practice Midwife1972176279
- Marlena DagostinFamily Nurse Practitioner1720578180
- Daniel Eberdt, FNP-CNurse Practitioner1780446427
- David Hansen, MDInternal Medicine Physician1689784878
- Melissa Normoyle, APRNFamily Nurse Practitioner1710535950
Verify Gregory S. Granzeier 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 036-094024Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
72% fewer Medicare Part D claims than the average obstetrics & gynecology physician in 2024
46 Medicare Part D claims for 21 beneficiaries, against an average of 165 among the 28,733 providers of this specialty who prescribed in Part D.
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.
Bills Medicare through one group practice
- Rockford Health PhysiciansRoscoe, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
4 obstetrics & gynecology physician records list a practice address in Roscoe
They are 4 of the 202 NPPES records with a practice address in Roscoe, and 2,062 obstetrics & gynecology physician records in Illinois.
All 4 in Roscoe → All 2,062 in Illinois → Every provider in Roscoe →
Other obstetrics & gynecology physician records in Illinois
- Anum Abbasi, MDChicago, IL1679063010
- Diane Abdel-Barry, M.D.Chicago, IL1508205808
- Rana Abdul-Khalek, MDRoscoe, IL1275768087
- Idries Abdur-Rahman, M.D.Ottawa, IL1891727236
- Jamil Abdur-Rahman, M.D.Gurnee, IL1710914189
- Bassel Abouzeid, MDPeoria, IL1376160846
- Ashley Abraham, M.D.Arlington Heights, IL1457615742
- Iris Abrahantes Morales, MDChicago, IL1164155164
- Fidel Abrego, MDChicago, IL1245351824
- Bayan AbunarAurora, IL1972063220
Common questions
What is Gregory S. Granzeier, DO's NPI number?
Gregory S. Granzeier, DO's National Provider Identifier (NPI) is 1134239320, issued on Aug 30, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Gregory S. Granzeier, DO located?
The NPPES record lists a practice address at 5000 Prairie Rose Dr, Roscoe, IL, 61073. Phone: (815) 971-2000. Providers update this record themselves, so call before visiting.
How can I verify Gregory S. Granzeier, DO's license?
NPPES lists Illinois license number 036-094024, 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 Gregory S. Granzeier, DO prescribe under Medicare Part D?
In 2024, Gregory S. Granzeier, DO had 46 Medicare Part D claims for 21 beneficiaries; the average among obstetrics & gynecology physician prescribers was 165. 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.