Richard Barton Day, MD
Internal Medicine Physician · Oceanside, CA
Richard Barton Day, MD is an internal medicine physician with a practice address in Oceanside, California, and NPI 1386716959, issued on Nov 15, 2006. Check the license (California A45298, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Richard Barton Day
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- A45298 CA
66794 TN
Self-reported in NPPES; status is on the state search - Practice location
- 3156 Vista Way, Oceanside, CA 92056
- Phone
- (760) 439-6581
- Enumerated
- Nov 15, 2006
- Record last updated
- Oct 2, 2024
- Medicaid ID
- 00A452980 CA
- Entity
- Type 1 · individual
Also registered at 3156 Vista Way
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Russell Holmes, MDSpecialist1598837163
- William Johnson, M.D.Diagnostic Radiology Physician1538266481
- Yung Le, MDSpecialist1275607020
- Michael Noud, M.D.Vascular & Interventional Radiology Physician1437443413
Verify Richard Barton Day in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A45298Check 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 internal medicine physician in 2024
45 Medicare Part D claims for 20 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 0% of claims.
Most prescribed
- Amlodipine Besylate12 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.
Internal Medicine Physician providers in California
There are 17,696 internal medicine physician records in California.
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Common questions
What is Richard Barton Day, MD's NPI number?
Richard Barton Day, MD's National Provider Identifier (NPI) is 1386716959, issued on Nov 15, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Richard Barton Day, MD located?
The NPPES record lists a practice address at 3156 Vista Way, Oceanside, CA, 92056. Phone: (760) 439-6581. Providers update this record themselves, so call before visiting.
How can I verify Richard Barton Day, MD's license?
NPPES lists California license number A45298, 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 Richard Barton Day, MD prescribe under Medicare Part D?
In 2024, Richard Barton Day, MD had 45 Medicare Part D claims for 20 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.