Dheeraj Mahajan, M.D.
Internal Medicine Physician · Oak Park, IL
Dheeraj Mahajan, M.D. is an internal medicine physician with a practice address in Oak Park, Illinois, and NPI 1831133693, issued on Jun 15, 2006. Check the license (Illinois 036106392, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Dheeraj Mahajan
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- 036106392 IL
036-106392 IL
Self-reported in NPPES; status is on the state search - Practice location
- 101 Madison St Ste 300, Oak Park, IL 60302
- Phone
- (708) 486-2700
- Enumerated
- Jun 15, 2006
- Record last updated
- Mar 17, 2026
- Fax
- (708) 486-2700
- Medicaid ID
- 036106392 IL
- Medicare enrollment
- Enrolled (PECOS I20040207000226); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,238 in Illinois → Look up another NPI →
Also registered at 101 Madison St Ste 300
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Farid Gholitabar, M.D.Cardiovascular Disease Physician1801278650
- Mujtaba Hussain, MBBSInternal Medicine Physician1255993309
- Renu Mahajan, MDHospice and Palliative Medicine (Physical Medicine & Rehabilitation) Physician1932311883
Verify Dheeraj Mahajan 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 036106392Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
7.0 times the Medicare Part D claims of the average internal medicine physician in 2024
22,074 Medicare Part D claims for 261 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 12% of claims. 16 claims were for opioids.
Most prescribed
- Atorvastatin Calcium1,815 claims
- Gabapentin888 claims
- Pantoprazole Sodium797 claims
- Metoprolol Succinate752 claims
- Eliquis740 claims
- Levothyroxine Sodium695 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
- Cimpar SCOak Park, IL
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Dheeraj Mahajan among 7,238 internal medicine physician records in Illinois
Dheeraj Mahajan, M.D. 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 2006, is newer than 7% of them.
- NPI issued2006 · 7% of these records are older, 61% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileYes · 50% of these records are
- Graduated1997 · median 2003 among the 3,580 with a school on file
- Record last updated2026 · 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).
62 internal medicine physician records list a practice address in Oak Park
They are 62 of the 2,307 NPPES records with a practice address in Oak Park, and 7,238 internal medicine physician records in Illinois.
All 7,238 in Illinois → Every provider in Oak Park → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Thomas Albert, D.C., M.D.Oak Park, IL 603021457465098
- Alejandra Campos, M.D.Oak Park, IL 603021932195146
- Wahiba Elhag, M.D.Oak Park, IL 603021982891826
- Augusto GuevaraOak Park, IL 603021962557686
- Charles Johnston, MDOak Park, IL 603021831288422
- Khurram Khan, M.D.Oak Park, IL 603021730370586
- Katarzyna Kielczyk, M.D.Oak Park, IL 603021194922203
- Esteban Linarez, M.D.Oak Park, IL 603021740483262
Common questions
What is Dheeraj Mahajan, M.D.'s NPI number?
Dheeraj Mahajan, M.D.'s National Provider Identifier (NPI) is 1831133693, issued on Jun 15, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Dheeraj Mahajan, M.D. located?
The NPPES record lists a practice address at 101 Madison St Ste 300, Oak Park, IL, 60302. Phone: (708) 486-2700. Providers update this record themselves, so call before visiting.
How can I verify Dheeraj Mahajan, M.D.'s license?
NPPES lists Illinois license number 036106392, 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 Dheeraj Mahajan, M.D. prescribe under Medicare Part D?
In 2024, Dheeraj Mahajan, M.D. had 22,074 Medicare Part D claims for 261 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.