Steven A. Johnson, MD
Internal Medicine Physician · Martinez, CA
Steven A. Johnson, MD is an internal medicine physician with a practice address in Martinez, California, and NPI 1861571531, issued on Nov 3, 2006. Check the license (California A79443, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Steven A. Johnson
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A79443 CA
Self-reported in NPPES; status is on the state search - Practice location
- 200 Muir RD, Martinez, CA 94553
- Phone
- (925) 372-1000
- Enumerated
- Nov 3, 2006
- Record last updated
- Dec 20, 2021 (not updated in 5 years: call before relying on the address or phone)
- Medicaid ID
- 00A794430 CA
- Medicare enrollment
- Enrolled (PECOS I20031223000563); accepts Medicare assignment
- Medical or professional school
- University Of California, Irvine, California College Of Medicine, 2000
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 200 Muir RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Steven A. Johnson in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A79443Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
98% fewer Medicare Part D claims than the average internal medicine physician in 2024
61 Medicare Part D claims for 49 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 26% of claims.
Most prescribed
- Adacel Tdap13 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
- Permanente Medical Group IncRichmond, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Steven A. Johnson among 17,696 internal medicine physician records in California
Steven A. Johnson, MD is one of 17,696 internal medicine physician records with a practice address in California. 79% 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 5% of them.
- NPI issued2006 · 5% of these records are older, 56% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2000 · median 2004 among the 11,065 with a school on file
- Record last updated2021 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
48 internal medicine physician records list a practice address in Martinez
They are 48 of the 1,816 NPPES records with a practice address in Martinez, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Martinez → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- David Chapman, MDMartinez, CA 945531578548129
- George Chuang, DOMartinez, CA 945531235217324
- Jeremy Fish, MDMartinez, CA 945531952497943
- Thomas Gamsky, MDMartinez, CA 945531043296247
- Gerhard Heinrich, M.D.Martinez, CA 945531306828728
- Nancy Lazarus, M.D.Martinez, CA 945531073598223
- Sara Levin, MDMartinez, CA 945531184707853
- Brian O'Neill, M.D.Martinez, CA 945531366425985
Common questions
What is Steven A. Johnson, MD's NPI number?
Steven A. Johnson, MD's National Provider Identifier (NPI) is 1861571531, issued on Nov 3, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Steven A. Johnson, MD located?
The NPPES record lists a practice address at 200 Muir RD, Martinez, CA, 94553. Phone: (925) 372-1000. Providers update this record themselves, so call before visiting.
How can I verify Steven A. Johnson, MD's license?
NPPES lists California license number A79443, 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 Steven A. Johnson, MD prescribe under Medicare Part D?
In 2024, Steven A. Johnson, MD had 61 Medicare Part D claims for 49 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.
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.