Registry data as of Aug 27, 2026

Kathleen Mayer, MD

Internal Medicine Physician · Bakersfield, CA

Kathleen Mayer, MD is an internal medicine physician with a practice address in Bakersfield, California, and NPI 1457488439, issued on Feb 27, 2007. Check the license (California C176095, 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, loaded Aug 27, 2026 · method · Verify with CMS →

NPPES recordas of Aug 27, 2026
1457488439
Name
Kathleen Mayer
Credential
MD
Primary taxonomy
Internal Medicine Physician 207R00000X
License numbers
C176095 CA
37902 CO
Self-reported in NPPES; status is on the state search
Practice location
4900 California Ave FL 2, Bakersfield, CA 93309
Phone
(617) 505-1520
Enumerated
Feb 27, 2007
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.
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Also registered at 4900 California Ave FL 2

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

  1. Lisa Gause, FNP-BCFamily Nurse Practitioner1932302973
  2. Melanie Madriaga, DOFamily Medicine Physician1144717836
  3. Niyoti Reddy, M.D.Endocrinology, Diabetes & Metabolism Physician1407207731

Verify Kathleen Mayer in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license C176095
    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.

Statewide context: the Medical Board of California reported 374 disciplinary actions in FY 2022-23. California discipline data →

230 internal medicine physician records list a Bakersfield practice address

They are 230 of the 11,539 NPPES records with a Bakersfield practice address, and 20,403 internal medicine physician records in California. No Medicare prescribing, quality score, industry payment or hospital affiliation is published for this NPI.

Other internal medicine physician records in California

  1. Jacob Aaron, MDSan Francisco, CA1407202518
  2. Alistair Aaronson, MDStanford, CA1457628760
  3. Jose Abad., MDSacramento, CA1144607219
  4. Donna Abare, MDOakland, CA1386722155
  5. Marce AbareScotts Valley, CA1457744708
  6. Samuel Abarte, M.D.Chula Vista, CA1578535498
  7. Alexander Abary, MDLong Beach, CA1104995919
  8. Luba Abascal, MDSan Francisco, CA1023180874
  9. Michael Abate, MDSacramento, CA1548248131
  10. Wali Abawi, D.O.Joshua Tree, CA1104362268

Common questions

What is Kathleen Mayer, MD's NPI number?

Kathleen Mayer, MD's National Provider Identifier (NPI) is 1457488439, issued on Feb 27, 2007. An NPI identifies a provider in billing; it is not a license.

Where is Kathleen Mayer, MD located?

The NPPES record lists a practice address at 4900 California Ave FL 2, Bakersfield, CA, 93309. Phone: (617) 505-1520. Providers update this record themselves, so call before visiting.

How can I verify Kathleen Mayer, MD's license?

NPPES lists California license number C176095, 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), loaded Aug 27, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. An NPI identifies who bills; it is not a license.

Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.