NPPES file of Aug 9, 2026

Internal Medicine Physician in California

17,696 NPPES records list internal medicine physician with a practice address in California, 45 per 100,000 residents, the 17th highest rate of 51. Los Angeles and San Francisco have the most; each record links to the provider's NPI and the California license search. Page 354 of 354.

CMS NPPES registry, file of Aug 9, 2026; 2023 Census estimates · NUCC 207R00000X · method

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

Los Angeles has the most, 1,423

  1. Los Angeles1,423
  2. San Francisco1,318
  3. San Diego961
  4. Sacramento601
  5. Oakland432

Internal Medicine Physician records in California

  1. Debralynne Zickafoose, M.D.Murrieta, CA 925621265406797
  2. Michael Ziegler, M.D.San Diego, CA 921031063526150
  3. Susan Ziemba, MDSanta Maria, CA 934541427065978
  4. Michael Zigelman, MDArroyo Grande, CA 934201003276494
  5. Thomas Zikos, M.D.Stanford, CA 943051801162904
  6. Christopher Zimmerman, MD, MPHSanta Ana, CA 927061891018065
  7. Aung Zin, M.D.Patton, CA 923691740249333
  8. Kyi Zin, M.D.Sacramento, CA 958331326213638
  9. Alexandra Zindman, MDSanta Monica, CA 904041699251181
  10. Stefan Zineski, M.D.Jackson, CA 956421801807995
  11. John Zingheim, M.D.Roseville, CA 956611821198821
  12. David Zingmond, MDLos Angeles, CA 900951306866595
  13. John Zipperer, MDLos Angeles, CA 900491649212770
  14. Douglas Ziprick, MDVictorville, CA 923951568518488
  15. Howard Zisser, M.D.Santa Barbara, CA 931051467561605
  16. Elad Ziv, MDSan Francisco, CA 941431750346474
  17. Tal Ziv, MDOakland, CA 946111508938259
  18. Paolo Zizzo, D.O.Carlsbad, CA 920081396750279
  19. Steven Zizzo, MD MPH CCFP DABOM OHDel Mar, CA 920141821854910
  20. Douglas Zlock, M.D.Walnut Creek, CA 945971427082692
  21. Ronald Zlotolow, M.D.Los Angeles, CA 900061407981301
  22. Hamidreza ZohoorkariFresno, CA 937201487217535
  23. Mahshid ZohouriFresno, CA 937011043953318
  24. Elaine Zollner, MDPanorama City, CA 914021821157488
  25. Parvaneh Zolnouni, MDNorwalk, CA 906501447206156
  26. Ingeborg Zoppoth, M.D.San Francisco, CA 941151780021766
  27. Barooyr Zorthian, MDOakland, CA 946021043294853
  28. Rong Zou, M.D.Poway, CA 920641154355659
  29. Muhammad Zubair, M.D.Elk Grove, CA 957571891755344
  30. Hijab Zubairi, M.D.Santa Clarita, CA 913551528384179
  31. Victor Zucker, MDMission Hills, CA 913451780603167
  32. Nora ZuhdiRiverside, CA 925011902556590
  33. Stephen Zukotynski, MDBellflower, CA 907061275681223
  34. Donna Zulman, M.D.Stanford, CA 943051144343278
  35. Jose Zumba, MDSacramento, CA 958171932660420
  36. Donald ZumwaltSan Francisco, CA 941151457489825
  37. Eugenia Zumwalt, D.O.San Leandro, CA 945771083032833
  38. Tony Zung, M.D.Walnut Creek, CA 945951508878638
  39. Joshua Zuniga, MDLos Angeles, CA 900331538662309
  40. John Zuorski, M.D.Walnut Creek, CA 945971487672473
  41. Eugenia ZweibachFoothill Ranch, CA 926101710410550
  42. Adam Zweig, MDSan Diego, CA 921031265527600
  43. Jonathan Zweig, MDRedwood City, CA 940631174601736
  44. Loretta Zweig, MDSanta Rosa, CA 954031538219357
  45. Liane Zwetzich, MDPacific Palisades, CA 902721346869955
  46. Robert Zylstra, MDSanta Barbara, CA 931051174652465

Source: CMS NPPES, primary taxonomy 207R00000X: records by practice city and the list of records, file of Aug 9, 2026.

California ranks 17 of 51 per resident

  1. New Jersey50
  2. New Hampshire48
  3. Minnesota46
  4. California45
  5. Florida45
  6. Ohio45
  7. 50 states and D.C.44

Source: CMS NPPES, primary taxonomy 207R00000X by practice state, file of Aug 9, 2026; records per 100,000 residents, 2023 Census estimates.

79.5% of these records appear in a Medicare file, against 78.7% nationally

A Medicare file here is Part D prescribing (2024), a MIPS score (2023), an Open Payments record (2024) or Medicare group billing (CMS Doctors and Clinicians). A record outside them may still see patients: these files cover Medicare only.

  1. California79.5%
  2. United States78.7%

Internal Medicine Physician records in California, measured

  • In a Medicare file14,068 of 17,696 · 79.5% here, 78.7% nationally
  • In the CMS Doctors and Clinicians file11,077 · 62.6% here, 61.4% nationally
  • Not updated in five years or more10,832 · 61.2% here, 55.4% nationally
  • Median graduation year2004 · the 11,065 records with a school on file

Source: CMS NPPES, file of Aug 9, 2026 (primary taxonomy 207R00000X); CMS Medicare Part D Prescribers 2024, MIPS 2023, Open Payments 2024 and Doctors and Clinicians, matched by NPI.

What the count covers

17,696 NPPES records list internal medicine physician (207R00000X) as their primary taxonomy with a practice address in California: 45 per 100,000 residents against 44 nationally (50 states and D.C.). Los Angeles has 1,423 of them (8%).

A record is a registration a provider made and keeps up to date: it shows neither that the provider is licensed nor that they still practice there. The state's own license search is the check.

States with a similar number

  1. New York12,067
  2. Florida10,151
  3. Texas9,175
  4. Pennsylvania7,300

States with a similar rate per 100,000

  1. Minnesota45.9
  2. Ohio44.8
  3. New Hampshire48.0
  4. Maine42.8

The largest states

  1. New York12,067
  2. Florida10,151
  3. Texas9,175
  4. Pennsylvania7,300
  5. Illinois7,238

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy; 2023 Census population estimates. A registry record 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.