Warren Chang, MD
Nephrology Physician · Daly City, CA
Warren Chang, MD is a nephrology physician with a practice address in Daly City, California, and NPI 1083674550, issued on Mar 27, 2006. Check the license (California AG9500, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Warren Chang
- Credential
- MD
- Primary taxonomy
- Nephrology Physician 207RN0300X
- License number
- AG9500 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1498 Southgate Ave, Daly City, CA 94015
- Phone
- (650) 755-4492
- Enumerated
- Mar 27, 2006
- Record last updated
- Aug 26, 2019 (not updated in 7 years: call before relying on the address or phone)
- Fax
- (650) 755-4466
- Medicaid ID
- 00A695000 CA
- Medicare enrollment
- Enrolled (PECOS I20050523000831); accepts Medicare assignment
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest nephrology physician records → All 1,468 in California → Look up another NPI →
Also registered at 1498 Southgate Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Zerina Bangawan, FNPFamily Nurse Practitioner1508163213
- Christian Cruz, MDNephrology Physician1023182227
- Philip Hertz, MDNephrology Physician1760443725
- Albert Kao, MDNephrology Physician1225099286
- Ruth Ramos, NP-CFamily Nurse Practitioner1194162859
- Robert Tseng, MDNephrology Physician1053371559
Verify Warren Chang in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license AG9500Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
49% more Medicare Part D claims than the average nephrology physician in 2024
2,178 Medicare Part D claims for 319 beneficiaries, against an average of 1,465 among the 10,986 providers of this specialty who prescribed in Part D. Brand-name drugs were 22% of claims.
Most prescribed
- Farxiga188 claims
- Hydralazine Hcl177 claims
- Amlodipine Besylate174 claims
- Losartan Potassium124 claims
- Furosemide89 claims
- Calcitriol86 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: $1,421.14
58 payments; by number, the most common kind was food and beverage; the largest payer was AstraZeneca Pharmaceuticals LP. The 8,230 providers of this specialty with any payment received $3,091.37 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 2 group practices
- North East Medical ServicesSan Francisco, CA
- West Coast KidneyDaly City, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Warren Chang among 1,468 nephrology physician records in California
Warren Chang, MD is one of 1,468 nephrology physician records with a practice address in California. 88% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 10% of them.
- NPI issued2006 · 10% of these records are older, 48% newer
- In a Medicare fileYes · 88% of these records are
- In the CMS Doctors and Clinicians fileYes · 77% of these records are
- Graduated1998 · median 2001 among the 1,128 with a school on file
- Record last updated2019 · 62% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RN0300X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Nephrology Physician providers in California
There are 1,468 nephrology physician records in California.
All 1,468 in California → Every provider in Daly City → Nephrology Physician nationwide →
The 8 nephrology physician records with the nearest ZIP codes
- Daniel Angeli, MDDaly City, CA 940151326417916
- Christian Cruz, MDDaly City, CA 940151023182227
- Philip Hertz, MDDaly City, CA 940151760443725
- Albert Kao, MDDaly City, CA 940151225099286
- Aung Kyaw Maung, M.DDaly City, CA 940151518288877
- Josephus-Ian Sanjorjo, MDDaly City, CA 940151073808168
- Hector Santiesteban, MEDICAL DOCTORDaly City, CA 940151245235738
- Robert Tseng, MDDaly City, CA 940151053371559
Common questions
What is Warren Chang, MD's NPI number?
Warren Chang, MD's National Provider Identifier (NPI) is 1083674550, issued on Mar 27, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Warren Chang, MD located?
The NPPES record lists a practice address at 1498 Southgate Ave, Daly City, CA, 94015. Phone: (650) 755-4492. Providers update this record themselves, so call before visiting.
How can I verify Warren Chang, MD's license?
NPPES lists California license number AG9500, 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 Warren Chang, MD prescribe under Medicare Part D?
In 2024, Warren Chang, MD had 2,178 Medicare Part D claims for 319 beneficiaries; the average among nephrology physician prescribers was 1,465. 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.