Nathan D. Ontrop, M.D.
Psychiatry Physician · Chicago, IL
Nathan D. Ontrop, M.D. is a psychiatry physician with a practice address in Chicago, Illinois, and NPI 1760778468, issued on Jun 22, 2011. Check the license (Illinois 036133952, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Nathan D. Ontrop
- Credential
- M.D.
- Primary taxonomy
- Psychiatry Physician 2084P0800X
- License numbers
- 036133952 IL
125059575 IL
Self-reported in NPPES; status is on the state search - Practice location
- 25 E Washington St Ste 1601, Chicago, IL 60602
- Phone
- (312) 725-2347
- Enumerated
- Jun 22, 2011
- Record last updated
- Aug 7, 2025
- Fax
- (312) 577-1574
- Medicare enrollment
- Enrolled (PECOS I20150707001683); accepts Medicare assignment
- Medical or professional school
- Loyola University Of Chicago, Stritch School Of Medicine, 2011
- Entity
- Type 1 · individual
8 nearest psychiatry physician records → All 2,147 in Illinois → Look up another NPI →
Also registered at 25 E Washington St Ste 1601
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Nicole Blythe, DNP, PMHNP-BCPsychiatric/Mental Health Nurse Practitioner1710595111
- Mary Catherine ChaseSocial Worker1265097455
- Katie Edwards-Humpal, NP-CFamily Nurse Practitioner1255880555
- Cynthia Hayes, LCSWClinical Social Worker1134973985
- Alecia Hurley, DNP, APRN, PMHNPPsychiatric/Mental Health Nurse Practitioner1386303444
- Deanne Pisarkiewicz, MDPsychiatry Physician1528633633
Verify Nathan D. Ontrop 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 036133952Check 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 psychiatry physician in 2024
280 Medicare Part D claims for 46 beneficiaries, against an average of 1,000 among the 35,054 providers of this specialty who prescribed in Part D.
Most prescribed
- Pregabalin28 claims
- Gabapentin23 claims
- Lamotrigine19 claims
- Trazodone Hcl17 claims
- Escitalopram Oxalate14 claims
- Hydroxyzine Hcl12 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.
Bills Medicare through 3 group practices
- Advocate Health And Hospitals CorporationOak Lawn, IL
- Osf Multi-Specialty GroupOttawa, IL
- Ottawa Regional Hospital And Healthcare CenterOttawa, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Nathan D. Ontrop among 2,147 psychiatry physician records in Illinois
Nathan D. Ontrop, M.D. is one of 2,147 psychiatry physician records with a practice address in Illinois. 69% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2011, is newer than 60% of them.
- NPI issued2011 · 60% of these records are older, 38% newer
- In a Medicare fileYes · 69% of these records are
- In the CMS Doctors and Clinicians fileYes · 41% of these records are
- Graduated2011 · median 2004 among the 877 with a school on file
- Record last updated2025 · 53% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2084P0800X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
841 psychiatry physician records list a practice address in Chicago
They are 841 of the 63,379 NPPES records with a practice address in Chicago, and 2,147 psychiatry physician records in Illinois.
All 2,147 in Illinois → Every provider in Chicago → Psychiatry Physician nationwide →
The 8 psychiatry physician records with the nearest ZIP codes
- Virginia Barry, M.D.Chicago, IL 606021306908967
- Henry Conroe, MDChicago, IL 606021811011760
- David Edelstein, M.D.Chicago, IL 606021679579155
- John Gottlieb, M.D.Chicago, IL 606021134295090
- Paul Holinger, MDChicago, IL 606021326162082
- Charles Jaffe, MDChicago, IL 606021679645923
- David Kaiser, M.D.Chicago, IL 606021285735779
- Christel Lembke, MDChicago, IL 606021053349969
Common questions
What is Nathan D. Ontrop, M.D.'s NPI number?
Nathan D. Ontrop, M.D.'s National Provider Identifier (NPI) is 1760778468, issued on Jun 22, 2011. An NPI identifies a provider in billing; it is not a license.
Where is Nathan D. Ontrop, M.D. located?
The NPPES record lists a practice address at 25 E Washington St Ste 1601, Chicago, IL, 60602. Phone: (312) 725-2347. Providers update this record themselves, so call before visiting.
How can I verify Nathan D. Ontrop, M.D.'s license?
NPPES lists Illinois license number 036133952, 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 Nathan D. Ontrop, M.D. prescribe under Medicare Part D?
In 2024, Nathan D. Ontrop, M.D. had 280 Medicare Part D claims for 46 beneficiaries; the average among psychiatry physician prescribers was 1,000. 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.