NPPES file of Aug 9, 2026

James Castles, M.D.

Rheumatology Physician · Davis, CA

James Castles, M.D. is a rheumatology physician with a practice address in Davis, California, and NPI 1477623403, issued on Nov 8, 2006. Check the license (California GFE25647, as entered in NPPES) on the Medical Board of California; the federal record below is the public data PlainDoctor holds for this provider.

Record from CMS NPPES, file of Aug 9, 2026 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1477623403
Name
James Castles
Credential
M.D.
Primary taxonomy
Rheumatology Physician 207RR0500X
License number
GFE25647 CA
Self-reported in NPPES; status is on the state search
Practice location
451 E. Health Sciences Drive, Davis, CA 95616
Phone
(530) 752-2884
Enumerated
Nov 8, 2006
Record last updated
Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
Fax
(530) 754-6047
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
Download card Updates feed

8 nearest rheumatology physician records → All 926 in California → Look up another NPI →

Also registered at 451 E. Health Sciences Drive

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Gurtej Cheema, M.D.Rheumatology Physician1578546578
  2. Merrill GershwinRheumatology Physician1881677268
  3. Dick Robbins, MDRheumatology Physician1972586352

Verify James Castles in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license GFE25647    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

Is this page about you? You can ask us to correct, restrict or remove it: how.

James Castles among 926 rheumatology physician records in California

James Castles, M.D. 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 not. Its NPI, issued in 2006, is newer than 6% of them.

  • NPI issued2006 · 6% of these records are older, 55% newer
  • In a Medicare fileNo · 81% of these records are
  • In the CMS Doctors and Clinicians fileNo · 69% of these records are
  • Record last updated2007 · 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. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.

All 926 in California → Every provider in Davis → Rheumatology Physician nationwide →

The 8 rheumatology physician records with the nearest ZIP codes

  1. Happy ChanDavis, CA 956161740409218
  2. Gurtej Cheema, M.D.Davis, CA 956161578546578
  3. Merrill GershwinDavis, CA 956161881677268
  4. Stanley Naguwa, M.D.Davis, CA 956161447231873
  5. Dick Robbins, MDDavis, CA 956161972586352
  6. Shraddha Jatwani, MDSacramento, CA 956201063641017
  7. Thitinan Srikulmontree, M.D.Citrus Heights, CA 956211699722603
  8. Christine Fernando, MDCarmichael, CA 956081962580605

Common questions

What is James Castles, M.D.'s NPI number?

James Castles, M.D.'s National Provider Identifier (NPI) is 1477623403, issued on Nov 8, 2006. An NPI identifies a provider in billing; it is not a license.

Where is James Castles, M.D. located?

The NPPES record lists a practice address at 451 E. Health Sciences Drive, Davis, CA, 95616. Phone: (530) 752-2884. Providers update this record themselves, so call before visiting.

How can I verify James Castles, M.D.'s license?

NPPES lists California license number GFE25647, 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.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

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.