John Ernzen, MD
Psychiatry Physician · Chicago, IL
John Ernzen, MD is a psychiatry physician with a practice address in Chicago, Illinois, and NPI 1346615663, issued on Dec 11, 2015. Check the license (Illinois 036157705, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- John Ernzen
- Credential
- MD
- Primary taxonomy
- Psychiatry Physician 2084P0800X
- License number
- 036157705 IL
Self-reported in NPPES; status is on the state search - Practice location
- 225 E Chicago Ave, Chicago, IL 60611
- Phone
- (312) 227-4000
- Enumerated
- Dec 11, 2015
- Record last updated
- May 27, 2022
- Medicare enrollment
- Enrolled (PECOS I20211230000573); accepts Medicare assignment
- Medical or professional school
- Northwestern University Feinberg Medical School, 2019
- Entity
- Type 1 · individual
8 nearest psychiatry physician records → All 2,147 in Illinois → Look up another NPI →
Also registered at 225 E Chicago Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Jasmene Abernathy, MDStudent in an Organized Health Care Education/Training Program1881454957
- Tamkeen Abreu, PHARMD, BCPSPharmacist Clinician (PhC)/ Clinical Pharmacy Specialist1366888653
- Matthew Abts, MDPediatric Pulmonology Physician1588989750
- Samuel AccordinoStudent in an Organized Health Care Education/Training Program1194525204
- Carly Adajian, DDSDentist1184373029
- Julie Adams, RDRegistered Dietitian1417569153
Verify John Ernzen 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 036157705Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
97% fewer Medicare Part D claims than the average psychiatry physician in 2024
33 Medicare Part D claims, against an average of 1,000 among the 35,054 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
- 2014 Health LLCDes Plaines, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
John Ernzen among 2,147 psychiatry physician records in Illinois
John Ernzen, MD 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 2015, is newer than 68% of them.
- NPI issued2015 · 68% of these records are older, 30% newer
- In a Medicare fileYes · 69% of these records are
- In the CMS Doctors and Clinicians fileYes · 41% of these records are
- Graduated2019 · median 2004 among the 877 with a school on file
- Record last updated2022 · 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
- Ghada Albeheary, MDChicago, IL 606111477534576
- Joan Anzia, MDChicago, IL 606111528039658
- Lydia Breen, MDChicago, IL 606111518926203
- Kenneth Cohen, M.D.Chicago, IL 606111952366551
- Pedro Dago, MDChicago, IL 606111689637639
- John Gerber, M.D.Chicago, IL 606111447216544
- Larry Goldman, M.D.Chicago, IL 606111851356752
- Jonathon Goldman, M.D.Chicago, IL 606111427013374
Common questions
What is John Ernzen, MD's NPI number?
John Ernzen, MD's National Provider Identifier (NPI) is 1346615663, issued on Dec 11, 2015. An NPI identifies a provider in billing; it is not a license.
Where is John Ernzen, MD located?
The NPPES record lists a practice address at 225 E Chicago Ave, Chicago, IL, 60611. Phone: (312) 227-4000. Providers update this record themselves, so call before visiting.
How can I verify John Ernzen, MD's license?
NPPES lists Illinois license number 036157705, 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 John Ernzen, MD prescribe under Medicare Part D?
In 2024, John Ernzen, MD had 33 Medicare Part D claims; 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.