William Shun Tzeng, MD
Internal Medicine Physician · Hacienda Heights, CA
William Shun Tzeng, MD is an internal medicine physician with a practice address in Hacienda Heights, California, and NPI 1649809385, issued on Apr 4, 2020. Check the license (California A187692, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- William Shun Tzeng
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- A187692 CA
Self-reported in NPPES; status is on the state search - Practice location
- 17170 Colima RD Ste G, Hacienda Heights, CA 91745
- Phone
- (626) 965-8202
- Enumerated
- Apr 4, 2020
- Record last updated
- Sep 3, 2025
- Fax
- (626) 964-9893
- Medicare enrollment
- Enrolled (PECOS I20230907002994); accepts Medicare assignment
- Medical or professional school
- Washington University School Of Medicine, 2020
- 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 17170 Colima RD Ste G
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Hsiu-Hung Su, FNP-CFamily Nurse Practitioner1710486725
Verify William Shun Tzeng in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A187692Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
57% fewer Medicare Part D claims than the average internal medicine physician in 2024
1,350 Medicare Part D claims for 233 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 19% of claims.
Most prescribed
- Atorvastatin Calcium112 claims
- Amlodipine Besylate78 claims
- Levothyroxine Sodium48 claims
- Metformin Hcl Er47 claims
- Losartan Potassium41 claims
- Tamsulosin Hcl39 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): 46.9 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: $1,001.98
36 payments; by number, the most common kind was food and beverage; the largest payer was Amgen 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
- Health Alliance Medical GroupHacienda Heights, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
William Shun Tzeng among 17,696 internal medicine physician records in California
William Shun Tzeng, 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 2020, is newer than 89% of them.
- NPI issued2020 · 89% of these records are older, 8% newer
- In a Medicare fileYes · 79% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated2020 · median 2004 among the 11,065 with a school on file
- Record last updated2025 · 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).
10 internal medicine physician records list a practice address in Hacienda Heights
They are 10 of the 597 NPPES records with a practice address in Hacienda Heights, and 17,696 internal medicine physician records in California.
All 17,696 in California → Every provider in Hacienda Heights → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- David Aron, MDHacienda Heights, CA 917451346319365
- Anthony Chen, M.D.Hacienda Heights, CA 917451073527099
- Jaw-Huei Chen, MDHacienda Heights, CA 917451194885384
- Show Shan Cherng, M.D.Hacienda Heights, CA 917451801827548
- Edmund Foo, M.D.Hacienda Heights, CA 917451881726354
- Ron Gu, MDHacienda Heights, CA 917451851494215
- Wendy Gu, M.D.Hacienda Heights, CA 917451740579994
- Ray Hsiao, MDHacienda Heights, CA 917451164507869
Common questions
What is William Shun Tzeng, MD's NPI number?
William Shun Tzeng, MD's National Provider Identifier (NPI) is 1649809385, issued on Apr 4, 2020. An NPI identifies a provider in billing; it is not a license.
Where is William Shun Tzeng, MD located?
The NPPES record lists a practice address at 17170 Colima RD Ste G, Hacienda Heights, CA, 91745. Phone: (626) 965-8202. Providers update this record themselves, so call before visiting.
How can I verify William Shun Tzeng, MD's license?
NPPES lists California license number A187692, 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 William Shun Tzeng, MD prescribe under Medicare Part D?
In 2024, William Shun Tzeng, MD had 1,350 Medicare Part D claims for 233 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is William Shun Tzeng, MD's MIPS final score?
The 2023 MIPS final score is 46.9 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.