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 231 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. Don Oh, M.D.Tustin, CA 927821326247669
  2. Edward Oh, MDFontana, CA 923351376284026
  3. Hee Oh, M.D.West Covina, CA 917901225106693
  4. Jai-Joon Oh, M.D.Clovis, CA 936191417388315
  5. Julie Oh, MDFountain Valley, CA 927081093389223
  6. Karen Oh, D.O.Torrance, CA 905051902006588
  7. Lucy Oh, MDSanta Rosa, CA 954031265516256
  8. Sun Oh, M.D.Calipatria, CA 922331689872319
  9. Sunah Oh, D.O.San Francisco, CA 941111447225396
  10. Timothy OhPasadena, CA 911051225395502
  11. Michael Ohabughiro, MDOakland, CA 946021003304866
  12. Junko Ohara, MDIrvine, CA 926181609434075
  13. Miwako Ohara-Hsu, M.D.Sacramento, CA 958161023451903
  14. Augustus Ohemeng, MDLakewood, CA 907121982603890
  15. Christine Ohikhuare, M.D.Anaheim, CA 928071841524675
  16. Cassandra Ohlsen, MDPacific Grove, CA 939501356457170
  17. Rachel OhmanLos Angeles, CA 900951912467135
  18. Khin Ohn, MDLos Angeles, CA 900121265925200
  19. Ajay Ohri, M.D.Oakland, CA 946021639523475
  20. Alka Ohri, M.DBakersfield, CA 933051508098617
  21. Kusum Ohri, M.D.Orange, CA 928681477692333
  22. Alison Ohringer, MDSan Francisco, CA 941431780379479
  23. Mika Ohtomo, M.D.Monrovia, CA 910161124384557
  24. Jon Oide, MDElk Grove, CA 957581083792717
  25. Jonathan Oishi, D.O.Irvine, CA 926181396109781
  26. Sheila Ojeaburu, MDStanford, CA 943051861132391
  27. Manisha Ojha, MDSan Francisco, CA 941021922070937
  28. Ekene Ojukwu, MDSan Francisco, CA 941101184014730
  29. Alfredo Ok, M.D.Harbor City, CA 907101265790760
  30. Belonwu Okafor, MDPanorama City, CA 914021902495815
  31. Tomoko Okahara, MDBellflower, CA 907061821140286
  32. Linda Okamoto, DODaly City, CA 940151902248289
  33. Neil Okamura, D.O.Danville, CA 945261437261781
  34. Tsuyoshi Okawa, M.D.Redondo Beach, CA 902771821105305
  35. Theodore Okerson, M.D.Thousand Oaks, CA 913201225170814
  36. Neelakshi Okhade, M.D.French Camp, CA 952311831282433
  37. Jean-Phillip Okhovat, MDPalo Alto, CA 943011497103105
  38. Helen Okoh, M.DBurbank, CA 915051396142956
  39. Augusta Okolo, MD, MSSacramento, CA 958171447990395
  40. Gisela Okonski, M.D.Redding, CA 960011518926559
  41. Uchenna Okoronkwo, MDOakland, CA 946051922025972
  42. Leonard Okun, MDSan Diego, CA 921231205941010
  43. Ivie Okundaye, MDPalo Alto, CA 943011679968077
  44. Marcel Okura, MDClovis, CA 936111629606553
  45. Ifunanyachukwu Okwuosa, MDTorrance, CA 905021023710456
  46. Lamberto Olaes, MDLos Angeles, CA 900291861592982
  47. Ronald Olah, MDPasadena, CA 911051881668341
  48. Michael Olalia, M.D.Union City, CA 945871477086320
  49. Alberta Olegario, MDBarstow, CA 923111053357012
  50. Lailey Naomi Oliva, MDLos Altos, CA 940221073768727

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.