Leonard Mark Oestreicher, MD
Family Medicine Physician · Merced, CA
Leonard Mark Oestreicher, MD is a family medicine physician with a practice address in Merced, California, and NPI 1033212022, issued on Sep 6, 2006. Check the license (California G29861, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Leonard Mark Oestreicher
- Credential
- MD
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- G29861 CA
Self-reported in NPPES; status is on the state search - Practice location
- 374 W Olive Avenue, Merced, CA 95348
- Phone
- (209) 383-3076
- Enumerated
- Sep 6, 2006
- Record last updated
- Dec 11, 2020 (not updated in 6 years: call before relying on the address or phone)
- Fax
- (209) 383-6301
- Medicaid ID
- 00G298610 CA
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 17,133 in California → Look up another NPI →
Also registered at 374 W Olive Avenue
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Dirk Mous, MDFamily Medicine Physician1538262522
Verify Leonard Mark Oestreicher in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G29861Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
99% fewer Medicare Part D claims than the average family medicine physician in 2024
49 Medicare Part D claims for 12 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 27% of 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.
Leonard Mark Oestreicher among 17,133 family medicine physician records in California
Leonard Mark Oestreicher, MD is one of 17,133 family 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 6% of them.
- NPI issued2006 · 6% of these records are older, 59% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileNo · 62% of these records are
- Record last updated2020 · 58% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
94 family medicine physician records list a practice address in Merced
They are 94 of the 2,836 NPPES records with a practice address in Merced, and 17,133 family medicine physician records in California.
All 17,133 in California → Every provider in Merced → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Brandon Boggs, MDMerced, CA 953481386655520
- Douglas Eck, MDMerced, CA 953481144323189
- Roger Fife, M.D.Merced, CA 953481548207590
- Eugenia Garcia, M.D.Merced, CA 953481265483622
- Charlie Kano, MDMerced, CA 953481003927567
- Daniel Leong, MDMerced, CA 953481518119510
- Grant Medefind, M.D.Merced, CA 953481437366069
- Dirk Mous, MDMerced, CA 953481538262522
Common questions
What is Leonard Mark Oestreicher, MD's NPI number?
Leonard Mark Oestreicher, MD's National Provider Identifier (NPI) is 1033212022, issued on Sep 6, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Leonard Mark Oestreicher, MD located?
The NPPES record lists a practice address at 374 W Olive Avenue, Merced, CA, 95348. Phone: (209) 383-3076. Providers update this record themselves, so call before visiting.
How can I verify Leonard Mark Oestreicher, MD's license?
NPPES lists California license number G29861, 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 Leonard Mark Oestreicher, MD prescribe under Medicare Part D?
In 2024, Leonard Mark Oestreicher, MD had 49 Medicare Part D claims for 12 beneficiaries; the average among family medicine physician prescribers was 3,544. 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.