James O. Posever, MD
Rheumatology Physician · Phoenix, AZ
James O. Posever, MD is a rheumatology physician with a practice address in Phoenix, Arizona, and NPI 1154364214, issued on Jun 14, 2006. Check the license (Arizona 29356, as entered in NPPES) on the Arizona Medical Board; the Medicare figures below come from public CMS files.
- Name
- James O. Posever
- Credential
- MD
- Primary taxonomy
- Rheumatology Physician 207RR0500X
- License number
- 29356 AZ
Self-reported in NPPES; status is on the state search - Practice location
- 4212 N 16TH St, Phoenix, AZ 85016
- Phone
- (602) 263-1200
- Enumerated
- Jun 14, 2006
- Record last updated
- Aug 26, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (602) 263-1593
- Medicaid ID
- 574584 AZ
- Medicare enrollment
- Enrolled (PECOS I20040506001357); accepts Medicare assignment
- Medical or professional school
- Northwestern University Feinberg Medical School, 1991
- Entity
- Type 1 · individual
8 nearest rheumatology physician records → All 117 in Arizona → Look up another NPI →
Also registered at 4212 N 16TH St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Andrea Aarseth, RNCritical Care Medicine Registered Nurse1235297292
- Deirdre Abellada, RN, PHNRegistered Nurse1710259395
- Joby Abraham, RNRegistered Nurse1376814046
- Frederick Abramek, MS, PHARMACISTPharmacist1528278736
- Karen AcostaRegistered Nurse1659748671
- Danton AdairRegistered Nurse1114387917
Verify James O. Posever in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersArizona Medical Board
Search for license 29356Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
64% fewer Medicare Part D claims than the average rheumatology physician in 2024
708 Medicare Part D claims for 88 beneficiaries, against an average of 1,978 among the 6,301 providers of this specialty who prescribed in Part D.
Most prescribed
- Hydroxychloroquine Sulfate86 claims
- Enbrel Sureclick62 claims
- Celecoxib55 claims
- Sulfasalazine50 claims
- Methotrexate49 claims
- Meloxicam43 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
- Dhew Ind Hlth SV Hlth Svs And Mntl Hlth AdmPhoenix, AZ
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
James O. Posever among 117 rheumatology physician records in Arizona
James O. Posever, MD is one of 117 rheumatology physician records with a practice address in Arizona. 86% 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 15% of them.
- NPI issued2006 · 15% of these records are older, 46% newer
- In a Medicare fileYes · 86% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated1991 · median 2001 among the 83 with a school on file
- Record last updated2011 · 40% 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 Arizona practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Rheumatology Physician providers in Arizona
There are 117 rheumatology physician records in Arizona.
All 117 in Arizona → Every provider in Phoenix → Rheumatology Physician nationwide →
The 8 rheumatology physician records with the nearest ZIP codes
- Dipika Patel-Boolani, MDPhoenix, AZ 850161316159544
- Lisa Sumner, MDPhoenix, AZ 850161962512012
- Nisha Manek, M.D.Phoenix, AZ 850151437139151
- Joseph Nolan, MDPhoenix, AZ 850151720026834
- James Clark, MDPhoenix, AZ 850141154954758
- Joanne Gurin, M.D.Phoenix, AZ 850141174581581
- Trent Smith, M.D.Phoenix, AZ 850181336110576
- Jeanne Attrep, M.D.Phoenix, AZ 850121710078209
Common questions
What is James O. Posever, MD's NPI number?
James O. Posever, MD's National Provider Identifier (NPI) is 1154364214, issued on Jun 14, 2006. An NPI identifies a provider in billing; it is not a license.
Where is James O. Posever, MD located?
The NPPES record lists a practice address at 4212 N 16TH St, Phoenix, AZ, 85016. Phone: (602) 263-1200. Providers update this record themselves, so call before visiting.
How can I verify James O. Posever, MD's license?
NPPES lists Arizona license number 29356, as entered by the provider. Search the Arizona Medical Board at https://www.azmd.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does James O. Posever, MD prescribe under Medicare Part D?
In 2024, James O. Posever, MD had 708 Medicare Part D claims for 88 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.