Clayton Chan, MD
Internal Medicine Physician · Oakland, CA
Clayton Chan, MD is an internal medicine physician with a practice address in Oakland, California, and NPI 1972682037, issued on Nov 2, 2006. Check the license (California A68139, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Clayton Chan
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A68139 CA
Self-reported in NPPES; status is on the state search - Practice location
- 818 Webster St, Oakland, CA 94607
- Phone
- (510) 986-6830
- Enumerated
- Nov 2, 2006
- Record last updated
- Jul 8, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (510) 986-6890
- Medicare enrollment
- Enrolled (PECOS I20100628001067); accepts Medicare assignment
- Medical or professional school
- New York Medical College, 1997
- Entity
- Type 1 · individual
Also registered at 818 Webster St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Christine Araneta, PAPhysician Assistant1780747238
- Gilbert Nolly ArcillaBehavior Technician1164046082
- Ivy CaiRegistered Nurse1982458915
- Yan CaiLicensed Vocational Nurse1477195717
- Florence ChanRegistered Nurse1649827593
- Sue Shu-Kwan Chan, M.D.Pediatrics Physician1497825988
Verify Clayton Chan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A68139Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
11% fewer Medicare Part D claims than the average internal medicine physician in 2024
2,829 Medicare Part D claims for 232 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 10% of claims.
Most prescribed
- Atorvastatin Calcium310 claims
- Amlodipine Besylate281 claims
- Metformin Hcl142 claims
- Lisinopril139 claims
- Losartan Potassium138 claims
- Metoprolol Succinate109 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
- Asian Health ServicesOakland, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (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 432 in Oakland → All 17,696 in California → Every provider in Oakland →
Other internal medicine physician records in California
- Jacob Aaron, MDSan Francisco, CA1407202518
- Alistair Aaronson, MDStanford, CA1457628760
- Jose Abad., MDSacramento, CA1144607219
- Donna Abare, MDOakland, CA1386722155
- Marce AbareScotts Valley, CA1457744708
- Samuel Abarte, M.D.Chula Vista, CA1578535498
- Alexander Abary, MDLong Beach, CA1104995919
- Luba Abascal, MDSan Francisco, CA1023180874
- Michael Abate, MDSacramento, CA1548248131
- Wali Abawi, D.O.Joshua Tree, CA1104362268
Common questions
What is Clayton Chan, MD's NPI number?
Clayton Chan, MD's National Provider Identifier (NPI) is 1972682037, issued on Nov 2, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Clayton Chan, MD located?
The NPPES record lists a practice address at 818 Webster St, Oakland, CA, 94607. Phone: (510) 986-6830. Providers update this record themselves, so call before visiting.
How can I verify Clayton Chan, MD's license?
NPPES lists California license number A68139, 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 Clayton Chan, MD prescribe under Medicare Part D?
In 2024, Clayton Chan, MD had 2,829 Medicare Part D claims for 232 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.