David Duc Diep, DO
Family Medicine Physician · Ontario, CA
David Duc Diep, DO is a family medicine physician with a practice address in Ontario, California, and NPI 1750651485, issued on Jan 11, 2012. Check the license (California 20A12549, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- David Duc Diep
- Credential
- DO
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- 20A12549 CA
Self-reported in NPPES; status is on the state search - Practice location
- 2295 S Vineyard Ave, Ontario, CA 91761
- Phone
- (713) 835-6235
- Enumerated
- Jan 11, 2012
- Record last updated
- Dec 3, 2021 (not updated in 5 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20150116001099); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 17,133 in California → Look up another NPI →
Also registered at 2295 S Vineyard Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Ana Mae Abaya, NPFamily Nurse Practitioner1255164943
- Sheila Marie Adan, D.O.Family Medicine Physician1912272733
- Anna Alley, CRNACertified Registered Nurse Anesthetist1518399732
- Hye Hyun An, PHARMDPharmacist1578428470
- Leonila Araneta, LCSWClinical Social Worker1861771974
- Fernando AvilaFamily Medicine Physician1396364147
Verify David Duc Diep in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A12549Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
71% more Medicare Part D claims than the average family medicine physician in 2024
6,049 Medicare Part D claims for 1,271 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 279 claims were for opioids.
Most prescribed
- Atorvastatin Calcium409 claims
- Amlodipine Besylate262 claims
- Lisinopril235 claims
- Losartan Potassium205 claims
- Metformin Hcl194 claims
- Hydrocodone-Acetaminophen193 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
- Southern California Permanente Medical GroupOntario, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
David Duc Diep among 17,133 family medicine physician records in California
David Duc Diep, DO 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 2012, is newer than 66% of them.
- NPI issued2012 · 66% of these records are older, 32% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 62% of these records are
- Graduated2011 · median 2005 among the 10,652 with a school on file
- Record last updated2021 · 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).
Family Medicine Physician providers in California
There are 17,133 family medicine physician records in California.
All 17,133 in California → Every provider in Ontario → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Sheila Marie Adan, D.O.Ontario, CA 917611912272733
- Fernando AvilaOntario, CA 917611396364147
- Judith Cabrera, MDOntario, CA 917611710202734
- Teodoro Diaz, DOOntario, CA 917611437190113
- Michaella Gaite, DOOntario, CA 917611154999522
- Kenneth Lee, M.D.Ontario, CA 917611750826863
- Andrelee Taganas, M.D.Ontario, CA 917611013171230
- Daniel TannousOntario, CA 917611508493040
Common questions
What is David Duc Diep, DO's NPI number?
David Duc Diep, DO's National Provider Identifier (NPI) is 1750651485, issued on Jan 11, 2012. An NPI identifies a provider in billing; it is not a license.
Where is David Duc Diep, DO located?
The NPPES record lists a practice address at 2295 S Vineyard Ave, Ontario, CA, 91761. Phone: (713) 835-6235. Providers update this record themselves, so call before visiting.
How can I verify David Duc Diep, DO's license?
NPPES lists California license number 20A12549, 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 David Duc Diep, DO prescribe under Medicare Part D?
In 2024, David Duc Diep, DO had 6,049 Medicare Part D claims for 1,271 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.