NPPES file of Aug 9, 2026

Mark Makoto Tanaka, M.D.

Emergency Medicine Physician · San Leandro, CA

Mark Makoto Tanaka, M.D. is an emergency medicine physician with a practice address in San Leandro, California, and NPI 1104904960, issued on Nov 1, 2006. Check the license (California A83467, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1104904960
Name
Mark Makoto Tanaka
Credential
M.D.
Primary taxonomy
Emergency Medicine Physician 207P00000X
License number
A83467 CA
Self-reported in NPPES; status is on the state search
Practice location
2500 Merced St, San Leandro, CA 94577
Phone
(510) 454-1000
Enumerated
Nov 1, 2006
Record last updated
Dec 9, 2021 (not updated in 5 years: call before relying on the address or phone)
Medicaid ID
00A834670 CA
Medicare enrollment
Enrolled (PECOS I20031215000564); accepts Medicare assignment
Medical or professional school
University Of California, San Francisco School Of Medicine, 1999
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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8 nearest emergency medicine physician records → All 7,751 in California → Look up another NPI →

Also registered at 2500 Merced St

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

  1. Rabiatu Abdullah, M.D.Emergency Medicine Physician1497833248
  2. Scott Abramson, M.D.Neurology Physician1891873667
  3. Jayaprada Achanta, M.D.Anesthesiology Physician1053463851
  4. Kristi Adachi, PHARMDPharmacist1396456737
  5. Mary Grace Aguayo, CRTCertified Respiratory Therapist1467923730
  6. Jatinder AhluwaliaPharmacist1508391483

Verify Mark Makoto Tanaka in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license A83467    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

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26% more Medicare Part D claims than the average emergency medicine physician in 2024

285 Medicare Part D claims for 194 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D. Brand-name drugs were 6% of claims. 15 claims were for opioids.

  1. Mark Tanaka285
  2. Specialty average226

Most prescribed

  1. Ondansetron Odt33 claims
  2. Moxifloxacin16 claims
  3. Ofloxacin13 claims
  4. Hydrocodone-Acetaminophen12 claims
  5. Doxycycline Monohydrate11 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

  1. Permanente Medical Group IncSan Leandro, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Mark Makoto Tanaka among 7,751 emergency medicine physician records in California

Mark Makoto Tanaka, M.D. is one of 7,751 emergency medicine 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. Its NPI, issued in 2006, is newer than 4% of them.

  • NPI issued2006 · 4% of these records are older, 60% newer
  • In a Medicare fileYes · 81% of these records are
  • In the CMS Doctors and Clinicians fileYes · 59% of these records are
  • Graduated1999 · median 2011 among the 4,560 with a school on file
  • Record last updated2021 · 59% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207P00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

59 emergency medicine physician records list a practice address in San Leandro

They are 59 of the 4,976 NPPES records with a practice address in San Leandro, and 7,751 emergency medicine physician records in California.

All 7,751 in California → Every provider in San Leandro → Emergency Medicine Physician nationwide →

The 8 emergency medicine physician records with the nearest ZIP codes

  1. Rabiatu Abdullah, M.D.San Leandro, CA 945771497833248
  2. Marc Andrews, M.D.San Leandro, CA 945771588743637
  3. Lewis Baker, M.D.San Leandro, CA 945771912085762
  4. George Brown, M.D.San Leandro, CA 945771174601660
  5. Calder Conner, MDSan Leandro, CA 945771770537433
  6. Brian Cutcliffe, M.D.San Leandro, CA 945771679652721
  7. Robert Fan, M.D.San Leandro, CA 945771316987977
  8. Jay Goldman, M.D.San Leandro, CA 945771427136282

Common questions

What is Mark Makoto Tanaka, M.D.'s NPI number?

Mark Makoto Tanaka, M.D.'s National Provider Identifier (NPI) is 1104904960, issued on Nov 1, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Mark Makoto Tanaka, M.D. located?

The NPPES record lists a practice address at 2500 Merced St, San Leandro, CA, 94577. Phone: (510) 454-1000. Providers update this record themselves, so call before visiting.

How can I verify Mark Makoto Tanaka, M.D.'s license?

NPPES lists California license number A83467, 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.

How much does Mark Makoto Tanaka, M.D. prescribe under Medicare Part D?

In 2024, Mark Makoto Tanaka, M.D. had 285 Medicare Part D claims for 194 beneficiaries; the average among emergency medicine physician prescribers was 226. 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.

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.