Michael Ma, MD
Internal Medicine Physician · San Gabriel, CA
Michael Ma, MD is an internal medicine physician with a practice address in San Gabriel, California, and NPI 1891945804, issued on Sep 26, 2008. Check the license (California A107326, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Michael Ma
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A107326 CA
Self-reported in NPPES; status is on the state search - Practice location
- 933 Walnut St, San Gabriel, CA 91776
- Phone
- (626) 372-5922
- Enumerated
- Sep 26, 2008
- Record last updated
- Nov 30, 2021 (not updated in 5 years: call before relying on the address or phone)
- Medicare enrollment
- Enrolled (PECOS I20100316000229); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 17,696 in California → Look up another NPI →
Verify Michael Ma in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A107326Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
37% fewer Medicare Part D claims than the average internal medicine physician in 2024
1,987 Medicare Part D claims for 305 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. 628 claims were for opioids.
Most prescribed
- Hydrocodone-Acetaminophen195 claims
- Oxycodone-Acetaminophen104 claims
- Morphine Sulfate Er70 claims
- Lactulose69 claims
- Gabapentin65 claims
- Lorazepam62 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
- Southern California Permanente Medical GroupOntario, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Michael Ma among 17,696 internal medicine physician records in California
Michael Ma, MD 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 2008, is newer than 56% of them.
- NPI issued2008 · 56% of these records are older, 40% 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 updated2021 · 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).
24 internal medicine physician records list a practice address in San Gabriel
They are 24 of the 762 NPPES records with a practice address in San Gabriel, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in San Gabriel → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Kenneth Chan, M.D.San Gabriel, CA 917761861422370
- Michelle Chan, M.D.San Gabriel, CA 917761043326283
- Araceli Chanbonpin, M.D.San Gabriel, CA 917761962572909
- Jennifer Chen, MDSan Gabriel, CA 917761548335516
- Le-Young Lee, MDSan Gabriel, CA 917761861417586
- Su Lee, M.D.San Gabriel, CA 917761871510370
- Charles Lin, MDSan Gabriel, CA 917761982719225
- Garry Pratt, MDSan Gabriel, CA 917761679592281
Common questions
What is Michael Ma, MD's NPI number?
Michael Ma, MD's National Provider Identifier (NPI) is 1891945804, issued on Sep 26, 2008. An NPI identifies a provider in billing; it is not a license.
Where is Michael Ma, MD located?
The NPPES record lists a practice address at 933 Walnut St, San Gabriel, CA, 91776. Phone: (626) 372-5922. Providers update this record themselves, so call before visiting.
How can I verify Michael Ma, MD's license?
NPPES lists California license number A107326, 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 Michael Ma, MD prescribe under Medicare Part D?
In 2024, Michael Ma, MD had 1,987 Medicare Part D claims for 305 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.