Hernan Gerardo Marcos, MD
Internal Medicine Physician · Chicago, IL
Hernan Gerardo Marcos, MD is an internal medicine physician with a practice address in Chicago, Illinois, and NPI 1134746142, issued on Jun 26, 2020. Check the license (Illinois 125076230, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Hernan Gerardo Marcos
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 125076230 IL
Self-reported in NPPES; status is on the state search - Practice location
- 1901 W Harrison St, Chicago, IL 60612
- Phone
- (312) 864-6000
- Enumerated
- Jun 26, 2020
- Record last updated
- Jun 26, 2020 (not updated in 6 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,238 in Illinois → Look up another NPI →
Also registered at 1901 W Harrison St
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Hernan Gerardo Marcos 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 125076230Check 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 internal medicine physician in 2024
94 Medicare Part D claims for 24 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 36% of claims.
Most prescribed
- Farxiga17 claims
- Atorvastatin Calcium14 claims
- Metoprolol Succinate11 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.
Industry payments in 2024: $396.07
3 payments; by number, the most common kind was food and beverage; the largest payer was Abbott Laboratories. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Hernan Gerardo Marcos among 7,238 internal medicine physician records in Illinois
Hernan Gerardo Marcos, 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 2020, is newer than 71% of them.
- NPI issued2020 · 71% of these records are older, 26% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileNo · 50% of these records are
- Record last updated2020 · 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).
2,867 internal medicine physician records list a practice address in Chicago
They are 2,867 of the 63,379 NPPES records with a practice address in Chicago, and 7,238 internal medicine physician records in Illinois.
All 7,238 in Illinois → Every provider in Chicago → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Keith Boyd, M.D.Chicago, IL 606121174591978
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- Henry Danko, M.D.Chicago, IL 606121780659524
- Denis Evans, M.D.Chicago, IL 606121952385841
- Tabassum Faruqi, M.D.Chicago, IL 606121013968536
- David Goldberg, MDChicago, IL 606121275588444
- Ionut Ilie, M.D.Chicago, IL 606121619926383
- Padma Kudaravalli, M.D.Chicago, IL 606121427004514
Common questions
What is Hernan Gerardo Marcos, MD's NPI number?
Hernan Gerardo Marcos, MD's National Provider Identifier (NPI) is 1134746142, issued on Jun 26, 2020. An NPI identifies a provider in billing; it is not a license.
Where is Hernan Gerardo Marcos, MD located?
The NPPES record lists a practice address at 1901 W Harrison St, Chicago, IL, 60612. Phone: (312) 864-6000. Providers update this record themselves, so call before visiting.
How can I verify Hernan Gerardo Marcos, MD's license?
NPPES lists Illinois license number 125076230, 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 Hernan Gerardo Marcos, MD prescribe under Medicare Part D?
In 2024, Hernan Gerardo Marcos, MD had 94 Medicare Part D claims for 24 beneficiaries; 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.