Catherine K. Buchanan, M.D.
Geriatric Medicine (Internal Medicine) Physician · Oakland, CA
Catherine K. Buchanan, M.D. is a geriatric medicine (internal medicine) physician with a practice address in Oakland, California, and NPI 1114903341, issued on Dec 20, 2005. Check the license (California A90592, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Catherine K. Buchanan
- Credential
- M.D.
- Primary taxonomy
- Geriatric Medicine (Internal Medicine) Physician 207RG0300X
- License number
- A90592 CA
Self-reported in NPPES; status is on the state search - Practice location
- 100 Bay PL, Oakland, CA 94610
- Phone
- (510) 891-8519
- Enumerated
- Dec 20, 2005
- Record last updated
- Dec 7, 2011 (not updated in 15 years: call before relying on the address or phone)
- Entity
- Type 1 · individual
8 nearest geriatric medicine (internal medicine) physician records → All 532 in California → Look up another NPI →
Also registered at 100 Bay PL
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Shelby Golightly, DPTPhysical Therapist1831832187
Verify Catherine K. Buchanan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A90592Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
93% fewer Medicare Part D claims than the average geriatric medicine (internal medicine) physician in 2024
298 Medicare Part D claims for 19 beneficiaries, against an average of 4,246 among the 3,116 providers of this specialty who prescribed in Part D. Brand-name drugs were 6% of claims.
Most prescribed
- Amlodipine Besylate22 claims
- Atorvastatin Calcium16 claims
- Levothyroxine Sodium14 claims
- Liothyronine Sodium14 claims
- Eliquis12 claims
- Trazodone Hcl12 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.
Catherine K. Buchanan among 532 geriatric medicine (internal medicine) physician records in California
Catherine K. Buchanan, M.D. is one of 532 geriatric medicine (internal medicine) physician records with a practice address in California. 77% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 93% newer
- In a Medicare fileYes · 77% of these records are
- In the CMS Doctors and Clinicians fileNo · 51% of these records are
- Record last updated2011 · 62% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0300X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Geriatric Medicine (Internal Medicine) Physician providers in California
There are 532 geriatric medicine (internal medicine) physician records in California.
All 532 in California → Every provider in Oakland → Geriatric Medicine (Internal Medicine) Physician nationwide →
The 8 geriatric medicine (internal medicine) physician records with the nearest ZIP codes
- Mala KrishnamoorthyOakland, CA 946111194145920
- James Mittelberger, M.D.Oakland, CA 946111508876194
- Samira Molaei, MDOakland, CA 946111053701466
- Timothy Parenteau, MD, PHDOakland, CA 946091790272599
- Julie Sandoval-Perry, MDOakland, CA 946111225180029
- Anuradha Shankar, MDOakland, CA 946111205914082
- Ali Torbati, MDOakland, CA 946111124384110
- Robert Tufft, MDOakland, CA 946091619010121
Common questions
What is Catherine K. Buchanan, M.D.'s NPI number?
Catherine K. Buchanan, M.D.'s National Provider Identifier (NPI) is 1114903341, issued on Dec 20, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Catherine K. Buchanan, M.D. located?
The NPPES record lists a practice address at 100 Bay PL, Oakland, CA, 94610. Phone: (510) 891-8519. Providers update this record themselves, so call before visiting.
How can I verify Catherine K. Buchanan, M.D.'s license?
NPPES lists California license number A90592, 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 Catherine K. Buchanan, M.D. prescribe under Medicare Part D?
In 2024, Catherine K. Buchanan, M.D. had 298 Medicare Part D claims for 19 beneficiaries; the average among geriatric medicine (internal medicine) physician prescribers was 4,246. 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.