Siddharth Tambar, MD
Rheumatology Physician · Chicago, IL
Siddharth Tambar, MD is a rheumatology physician with a practice address in Chicago, Illinois, and NPI 1477655488, issued on Sep 1, 2006. Check the license (Illinois 036-111655, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Siddharth Tambar
- Credential
- MD
- Primary taxonomy
- Rheumatology Physician 207RR0500X
- License number
- 036-111655 IL
Self-reported in NPPES; status is on the state search - Practice location
- 618 W Fulton St, Chicago, IL 60661
- Phone
- (773) 348-7171
- Enumerated
- Sep 1, 2006
- Record last updated
- Feb 25, 2026
- Fax
- (737) 348-7414
- Medicare enrollment
- Enrolled (PECOS I20050316001031); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest rheumatology physician records → All 340 in Illinois → Look up another NPI →
Also registered at 618 W Fulton St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Leah Brown, PA-C, MMSPhysician Assistant1780814525
- Elizabeth Kiracofe, M.D.Dermatology Physician1336400217
- Mitchell Sheinkop, M.D.Orthopaedic Surgery Physician1073592861
Verify Siddharth Tambar 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 036-111655Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
87% fewer Medicare Part D claims than the average rheumatology physician in 2024
248 Medicare Part D claims for 72 beneficiaries, against an average of 1,978 among the 6,301 providers of this specialty who prescribed in Part D. Brand-name drugs were 28% of claims. 20 claims were for opioids.
Most prescribed
- Prednisone37 claims
- Methotrexate29 claims
- Leflunomide24 claims
- Benlysta23 claims
- Hydroxychloroquine Sulfate18 claims
- Tramadol Hcl17 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: $682.85
26 payments; by number, the most common kind was food and beverage; the largest payer was Alexion Pharmaceuticals, Inc. The 4,486 providers of this specialty with any payment received $8,538.33 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.
Siddharth Tambar among 340 rheumatology physician records in Illinois
Siddharth Tambar, MD is one of 340 rheumatology physician records with a practice address in Illinois. 83% 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, 52% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 72% of these records are
- Graduated2001 · median 2003 among the 244 with a school on file
- Record last updated2026 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RR0500X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Rheumatology Physician providers in Illinois
There are 340 rheumatology physician records in Illinois.
All 340 in Illinois → Every provider in Chicago → Rheumatology Physician nationwide →
The 8 rheumatology physician records with the nearest ZIP codes
- Osman Bhatty, MDChicago, IL 606571124401500
- Yongsuk Lertratanakul, MDChicago, IL 606571215935663
- David Mael, M.D.Chicago, IL 606571134152739
- Abdul Mohammed, MBBS, MDChicago, IL 606571790102804
- Romesa SajjadChicago, IL 606571609371616
- Laarni Quimson, D.O.Chicago, IL 606431245671320
- Dorothy Bloniarz, M.D.Chicago, IL 606411841365939
- Manish Jain, M.D.Chicago, IL 606401417075581
Common questions
What is Siddharth Tambar, MD's NPI number?
Siddharth Tambar, MD's National Provider Identifier (NPI) is 1477655488, issued on Sep 1, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Siddharth Tambar, MD located?
The NPPES record lists a practice address at 618 W Fulton St, Chicago, IL, 60661. Phone: (773) 348-7171. Providers update this record themselves, so call before visiting.
How can I verify Siddharth Tambar, MD's license?
NPPES lists Illinois license number 036-111655, 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 Siddharth Tambar, MD prescribe under Medicare Part D?
In 2024, Siddharth Tambar, MD had 248 Medicare Part D claims for 72 beneficiaries; the average among rheumatology physician prescribers was 1,978. 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.