Diane E. Tjornhom, MD
Rheumatology Physician · Bellflower, CA
Diane E. Tjornhom, MD is a rheumatology physician with a practice address in Bellflower, California, and NPI 1649339235, issued on Dec 8, 2006. Check the license (California G73827, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Diane E. Tjornhom
- Credential
- MD
- Primary taxonomy
- Rheumatology Physician 207RR0500X
- License number
- G73827 CA
Self-reported in NPPES; status is on the state search - Practice location
- 9400 Rosecrans Ave, Bellflower, CA 90706
- Phone
- (562) 461-3000
- Enumerated
- Dec 8, 2006
- Record last updated
- Nov 29, 2021 (not updated in 5 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20100927000601); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest rheumatology physician records → All 926 in California → Look up another NPI →
Also registered at 9400 Rosecrans Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Basil Abdelkarim, MDInternal Medicine Physician1003968454
- Le Marie Abellon, NPNurse Practitioner1144389867
- Adrian Acevedo, MDEmergency Medicine Physician1407923303
- Pravin Acharya, MDEmergency Medicine Physician1104993088
- Michele Afshar, PAPhysician Assistant1013065952
- Maria Agbing-Mamangun, MDPsychiatry Physician1063589984
Verify Diane E. Tjornhom in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G73827Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
2% more Medicare Part D claims than the average rheumatology physician in 2024
2,020 Medicare Part D claims for 410 beneficiaries, against an average of 1,978 among the 6,301 providers of this specialty who prescribed in Part D. 215 claims were for opioids.
Most prescribed
- Methotrexate290 claims
- Hydroxychloroquine Sulfate233 claims
- Meloxicam122 claims
- Hydrocodone-Acetaminophen120 claims
- Prednisone106 claims
- Allopurinol89 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
- Southern California Permanente Medical GroupBellflower, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Diane E. Tjornhom among 926 rheumatology physician records in California
Diane E. Tjornhom, MD is one of 926 rheumatology physician records with a practice address in California. 81% 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 6% of them.
- NPI issued2006 · 6% of these records are older, 55% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 69% of these records are
- Graduated1989 · median 2003 among the 641 with a school on file
- Record last updated2021 · 62% 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 California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Rheumatology Physician providers in California
There are 926 rheumatology physician records in California.
All 926 in California → Every provider in Bellflower → Rheumatology Physician nationwide →
The 8 rheumatology physician records with the nearest ZIP codes
- Virginia Chan, MDBellflower, CA 907061891847273
- Gerald Levy, MDBellflower, CA 907061386715209
- Dipti Doshi, MDCerritos, CA 907031053325761
- Linnea Smith, PA-CCerritos, CA 907031275464927
- Rajinder Mahajan, MDHarbor City, CA 907101962550913
- Suchada Shu, MDHarbor City, CA 907101538236344
- Ivette Stickelmaier, MDLakewood, CA 907121962430579
- Rebekah Neal-Kraal, M.D.Los Alamitos, CA 907201215165667
Common questions
What is Diane E. Tjornhom, MD's NPI number?
Diane E. Tjornhom, MD's National Provider Identifier (NPI) is 1649339235, issued on Dec 8, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Diane E. Tjornhom, MD located?
The NPPES record lists a practice address at 9400 Rosecrans Ave, Bellflower, CA, 90706. Phone: (562) 461-3000. Providers update this record themselves, so call before visiting.
How can I verify Diane E. Tjornhom, MD's license?
NPPES lists California license number G73827, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Diane E. Tjornhom, MD prescribe under Medicare Part D?
In 2024, Diane E. Tjornhom, MD had 2,020 Medicare Part D claims for 410 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.