Darin O'Connor Harnisch, M.D.
Specialist · Niles, IL
Darin O'Connor Harnisch, M.D. is a specialist with a practice address in Niles, Illinois, and NPI 1710910880, issued on Jul 9, 2006. Check the license (Illinois 036-106895, as entered in NPPES) with the Illinois board that licenses this profession; the Medicare figures below come from public CMS files.
- Name
- Darin O'Connor Harnisch
- Credential
- M.D.
- Primary taxonomy
- Specialist 174400000X
- License number
- 036-106895 IL
Self-reported in NPPES; status is on the state search - Practice location
- 7900 N Milwaukee Ave, Niles, IL 60714
- Phone
- (847) 663-9400
- Enumerated
- Jul 9, 2006
- Record last updated
- Dec 20, 2021 (not updated in 5 years: call before relying on the address or phone)
- Fax
- (847) 663-9827
- Medicare enrollment
- Enrolled (PECOS I20040701000128); may accept Medicare assignment
- Medical or professional school
- Loyola University Of Chicago, Stritch School Of Medicine, 1998
- Entity
- Type 1 · individual
8 nearest specialist records → All 1,154 in Illinois → Look up another NPI →
Also registered at 7900 N Milwaukee Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Kayla Barango, MSN, APRN, FNP-CFamily Nurse Practitioner1912676123
- Ellen Brull, M.D.Family Medicine Physician1043396419
- Donna DziengielPharmacist1598114209
- Juan Engel, MDGastroenterology Physician1225122393
- Walter Falkowski, MDUrology Physician1124067335
- Debra Haley, PHDClinical Psychologist1306948690
Verify Darin O'Connor Harnisch in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersWhich Illinois board licenses this profession
Search for license 036-106895Check 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 specialist in 2024
382 Medicare Part D claims for 94 beneficiaries, against an average of 1,380 among the 8,233 providers of this specialty who prescribed in Part D. Brand-name drugs were 30% of claims.
Most prescribed
- Doxycycline Hyclate60 claims
- Descovy27 claims
- Cefadroxil24 claims
- Amoxicillin-Clavulanate Potass19 claims
- Ethambutol Hcl18 claims
- Rifampin18 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 one group practice
- Northwest Infectious Disease Consultants, S.C.Niles, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Darin O'Connor Harnisch among 1,154 specialist records in Illinois
Darin O'Connor Harnisch, M.D. is one of 1,154 specialist records with a practice address in Illinois. 19% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 8% of them.
- NPI issued2006 · 8% of these records are older, 58% newer
- In a Medicare fileYes · 19% of these records are
- In the CMS Doctors and Clinicians fileYes · 11% of these records are
- Graduated1998 · median 1988 among the 127 with a school on file
- Record last updated2021 · 84% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 174400000X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Specialist providers in Illinois
There are 1,154 specialist records in Illinois.
All 1,154 in Illinois → Every provider in Niles → Specialist nationwide →
The 8 specialist records with the nearest ZIP codes
- Marjerie Badilla, M.D.Niles, IL 607141467552653
- Eileen Dugan, LCSWLincolnwood, IL 607121538292875
- Nicole Hroma, SENIOR PTElmwood Park, IL 607071912050097
- Darlene Kelly, CTRSChicago, IL 607071508156381
- Amanda Loomis, CTRSChicago, IL 607071710271952
- Terry Stanek, MSPTElmwood Park, IL 607071972673150
- Linda Dudek-Francis, D.N.Harwood Heights, IL 607061699893842
- Ralph Francis, D.N.Harwood Heights, IL 607061558489708
Common questions
What is Darin O'Connor Harnisch, M.D.'s NPI number?
Darin O'Connor Harnisch, M.D.'s National Provider Identifier (NPI) is 1710910880, issued on Jul 9, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Darin O'Connor Harnisch, M.D. located?
The NPPES record lists a practice address at 7900 N Milwaukee Ave, Niles, IL, 60714. Phone: (847) 663-9400. Providers update this record themselves, so call before visiting.
How can I verify Darin O'Connor Harnisch, M.D.'s license?
NPPES lists Illinois license number 036-106895, as entered by the provider. Search the Illinois board that licenses this profession; the NPPES record confirms identity only.
How much does Darin O'Connor Harnisch, M.D. prescribe under Medicare Part D?
In 2024, Darin O'Connor Harnisch, M.D. had 382 Medicare Part D claims for 94 beneficiaries; the average among specialist prescribers was 1,380. 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.