Chao Sun, M.D.
Occupational Medicine Physician · Pleasanton, CA
Chao Sun, M.D. is an occupational medicine physician with a practice address in Pleasanton, California, and NPI 1013118884, issued on May 30, 2007. Check the license (California A101860, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Chao Sun
- Credential
- M.D.
- Primary taxonomy
- Occupational Medicine Physician 2083X0100X
- License number
- A101860 CA
Self-reported in NPPES; status is on the state search - Practice location
- 5700 Stoneridge Mall RD Ste 100, Pleasanton, CA 94588
- Phone
- (925) 915-9530
- Enumerated
- May 30, 2007
- Record last updated
- Aug 21, 2012 (not updated in 14 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20080206000312); may accept Medicare assignment
- Entity
- Type 1 · individual
8 nearest occupational medicine physician records → All 415 in California → Look up another NPI →
Verify Chao Sun in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A101860Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
25% fewer Medicare Part D claims than the average occupational medicine physician in 2024
595 Medicare Part D claims for 90 beneficiaries, against an average of 794 among the 463 providers of this specialty who prescribed in Part D. Brand-name drugs were 4% of claims.
Most prescribed
- Amlodipine Besylate53 claims
- Simvastatin45 claims
- Atorvastatin Calcium38 claims
- Metformin Hcl32 claims
- Levothyroxine Sodium26 claims
- Losartan Potassium24 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.
Industry payments in 2024: $55.11
1 payment: food and beverage; the largest payer was RxSight Inc. The 193 providers of this specialty with any payment received $2,381.67 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Chao Sun among 415 occupational medicine physician records in California
Chao Sun, M.D. is one of 415 occupational medicine physician records with a practice address in California. 30% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2007, is newer than 43% of them.
- NPI issued2007 · 43% of these records are older, 31% newer
- In a Medicare fileYes · 30% of these records are
- In the CMS Doctors and Clinicians fileYes · 12% of these records are
- Graduated1983 · median 1995 among the 51 with a school on file
- Record last updated2012 · 75% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2083X0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Occupational Medicine Physician providers in California
There are 415 occupational medicine physician records in California.
All 415 in California → Every provider in Pleasanton → Occupational Medicine Physician nationwide →
The 8 occupational medicine physician records with the nearest ZIP codes
- Stephen Nord, MDPleasanton, CA 945881255484689
- Jeffrey Gao, MDVallejo, CA 945891710065552
- Brian Knapp, MDVallejo, CA 945891528146362
- Susan Lambert, MDVallejo, CA 945891720166549
- Rose Melgar, M.D.Union City, CA 945871386716199
- Charlene Niizawa, M.D.Union City, CA 945871558449314
- Michael Palomino, MDVallejo, CA 945891992883706
- Phillip Wagner, MDVallejo, CA 945891912931619
Common questions
What is Chao Sun, M.D.'s NPI number?
Chao Sun, M.D.'s National Provider Identifier (NPI) is 1013118884, issued on May 30, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Chao Sun, M.D. located?
The NPPES record lists a practice address at 5700 Stoneridge Mall RD Ste 100, Pleasanton, CA, 94588. Phone: (925) 915-9530. Providers update this record themselves, so call before visiting.
How can I verify Chao Sun, M.D.'s license?
NPPES lists California license number A101860, 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 Chao Sun, M.D. prescribe under Medicare Part D?
In 2024, Chao Sun, M.D. had 595 Medicare Part D claims for 90 beneficiaries; the average among occupational medicine physician prescribers was 794. 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.