Diego Rafael Fernandez, M.D.
Internal Medicine Physician · Oakland, CA
Diego Rafael Fernandez, M.D. is an internal medicine physician with a practice address in Oakland, California, and NPI 1871957712, issued on Apr 6, 2016. Check the license (California A172321, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Diego Rafael Fernandez
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- A172321 CA
MD.36555 AL
Self-reported in NPPES; status is on the state search - Practice location
- 350 Hawthorne Ave Ste 2308, Oakland, CA 94609
- Phone
- (510) 869-6883
- Enumerated
- Apr 6, 2016
- Record last updated
- Apr 15, 2022
- Fax
- (510) 869-6888
- Medicare enrollment
- Enrolled (PECOS I20210915003346); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 350 Hawthorne Ave Ste 2308
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Arya Mansouri, M.D.Internal Medicine Physician1760802847
Verify Diego Rafael Fernandez in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A172321Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
92% fewer Medicare Part D claims than the average internal medicine physician in 2024
252 Medicare Part D claims for 110 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 14% of claims. 11 claims were for opioids.
Most prescribed
- Atorvastatin Calcium17 claims
- Furosemide15 claims
- Prednisone13 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
- Sutter Bay Medical FoundationOakland, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Diego Rafael Fernandez among 17,696 internal medicine physician records in California
Diego Rafael Fernandez, M.D. 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 2016, is newer than 79% of them.
- NPI issued2016 · 79% of these records are older, 19% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2016 · median 2004 among the 11,065 with a school on file
- Record last updated2022 · 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).
432 internal medicine physician records list a practice address in Oakland
They are 432 of the 18,558 NPPES records with a practice address in Oakland, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Oakland → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Rachel Callaghan, M.D.Oakland, CA 946091548239627
- Samuel Dong, MDOakland, CA 946091528027471
- Amy Garlin, M.D.Oakland, CA 946091346269719
- Marci Gottlieb, MDOakland, CA 946091194785428
- Christopher Hall, M.D.Oakland, CA 946091295754729
- John Jones, MDOakland, CA 946091639139967
- Michael Kim, MDOakland, CA 946091477513703
- Pandora Lee, M.D.Oakland, CA 946091598725327
Common questions
What is Diego Rafael Fernandez, M.D.'s NPI number?
Diego Rafael Fernandez, M.D.'s National Provider Identifier (NPI) is 1871957712, issued on Apr 6, 2016. An NPI identifies a provider in billing; it is not a license.
Where is Diego Rafael Fernandez, M.D. located?
The NPPES record lists a practice address at 350 Hawthorne Ave Ste 2308, Oakland, CA, 94609. Phone: (510) 869-6883. Providers update this record themselves, so call before visiting.
How can I verify Diego Rafael Fernandez, M.D.'s license?
NPPES lists California license number A172321, 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 Diego Rafael Fernandez, M.D. prescribe under Medicare Part D?
In 2024, Diego Rafael Fernandez, M.D. had 252 Medicare Part D claims for 110 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.