Mu-Chien Chiang, D.O.
Internal Medicine Physician · San Marino, CA
Mu-Chien Chiang, D.O. is an internal medicine physician with a practice address in San Marino, California, and NPI 1831322148, issued on Sep 2, 2009. Check the license (California 20A11321, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mu-Chien Chiang
- Credential
- D.O.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 20A11321 CA
Self-reported in NPPES; status is on the state search - Practice location
- 375 Huntington Dr, San Marino, CA 91108
- Phone
- (626) 441-4231
- Enumerated
- Sep 2, 2009
- Record last updated
- Dec 10, 2015 (not updated in 11 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20101109001026); accepts Medicare assignment
- Medical or professional school
- New York College Of Osteo Medicine Of New York Institute Of Technology, 2006
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Also registered at 375 Huntington Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Lorna Blanco, M.D.Specialist1093787178
- Sonya Chen-Hsieh, MDFamily Medicine Physician1528017894
- Louis Countryman, M.D.Specialist1184612327
- Chien Fang, MDInternal Medicine Physician1922071398
- Jeffrey Huang, D.O.Ophthalmology Physician1124274998
- Emily McDowell, PA-CPhysician Assistant1659704286
Verify Mu-Chien Chiang in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A11321Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
13% fewer Medicare Part D claims than the average internal medicine physician in 2024
2,772 Medicare Part D claims for 351 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. 89 claims were for opioids.
Most prescribed
- Rosuvastatin Calcium213 claims
- Amlodipine Besylate210 claims
- Atorvastatin Calcium188 claims
- Losartan Potassium145 claims
- Metformin Hcl104 claims
- Lisinopril79 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.
The practice group's MIPS final score for 2023 (Medicare payment program): 80.5 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $513.78
4 payments; by number, the most common kind was food and beverage; the largest payer was Novo Nordisk Inc. The 50,334 providers of this specialty with any payment received $1,303.06 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.
Bills Medicare through one group practice
- The Huntington Medical FoundationSan Marino, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mu-Chien Chiang among 17,696 internal medicine physician records in California
Mu-Chien Chiang, D.O. is one of 17,696 internal medicine physician records with a practice address in California. 79% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2009, is newer than 60% of them.
- NPI issued2009 · 60% of these records are older, 37% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2006 · median 2004 among the 11,065 with a school on file
- Record last updated2015 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
11 internal medicine physician records list a practice address in San Marino
They are 11 of the 184 NPPES records with a practice address in San Marino, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in San Marino → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Elisa Alvarado, M.D.San Marino, CA 911081891979746
- Derek Cheung, MDSan Marino, CA 911081336671981
- Sonya Ehresmann, M.D.San Marino, CA 911081750533212
- Chien Fang, MDSan Marino, CA 911081922071398
- Sabrina Hong, MDSan Marino, CA 911081164750394
- Ya-Gin Hanna Huang, MDSan Marino, CA 911081265012520
- Ralph Jung, MDPasadena, CA 911081831436831
- Thomas Maxwell, M.D.San Marino, CA 911081598806655
Common questions
What is Mu-Chien Chiang, D.O.'s NPI number?
Mu-Chien Chiang, D.O.'s National Provider Identifier (NPI) is 1831322148, issued on Sep 2, 2009. An NPI identifies a provider in billing; it is not a license.
Where is Mu-Chien Chiang, D.O. located?
The NPPES record lists a practice address at 375 Huntington Dr, San Marino, CA, 91108. Phone: (626) 441-4231. Providers update this record themselves, so call before visiting.
How can I verify Mu-Chien Chiang, D.O.'s license?
NPPES lists California license number 20A11321, 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 Mu-Chien Chiang, D.O. prescribe under Medicare Part D?
In 2024, Mu-Chien Chiang, D.O. had 2,772 Medicare Part D claims for 351 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is Mu-Chien Chiang, D.O.'s MIPS final score?
The 2023 MIPS final score is 80.5 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
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.