Doctor profile · Federal record

Dr. Matthew Chang, M.D.

Gastroenterology Physician (CMS: Gastroenterology) · Internal Medicine Physician · Internal Medicine Physician · Palo Alto, CA

  • NPI 1598949521
  • Accepts Medicare
  • 20 yrs in practice
  • Licensed in 3 states
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
900 Blake Wilbur Dr
Palo Alto, CA 943042201
(650) 736-5555

Credentials & registration

NPPES · NUCC
NPI registered
December 2007 — 19 yrs on file
Profile last updated
December 17, 2021
Year of graduation
2006 — 20 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State licenses (3)
California #A133674 · Massachusetts #250090 · New York #245746

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1598949521. Last verified May 11, 2026.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$24
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 1 $24.05

By nature of payment

Food and Beverage
$24

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
479
Patients
310
Total drug cost
$160,158
Drug Type Claims Patients Total cost
Gavilyte-C (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 276 274 $5,900
Pantoprazole Sodium Generic 62 36 $2,655
Xifaxan (Rifaximin) Brand 39 0 $142,503
Ursodiol Generic 31 0 $6,012
Omeprazole Generic 18 0 $273
Lactulose Generic 17 0 $1,098
Azathioprine Generic 13 0 $303
Furosemide Generic 12 0 $132
Twinrix (Hepatitis A and B Vaccine/Pf) Brand 11 0 $1,281

Frequently asked questions

Auto-generated from federal data
What is Dr. Matthew Chang's medical specialty?
Dr. Matthew Chang practices Gastroenterology Physician in Palo Alto, CA.
Where does Dr. Matthew Chang practice?
Dr. Matthew Chang practices at 900 Blake Wilbur Dr, Palo Alto, CA 943042201. Office phone: 6507365555.
What is Dr. Matthew Chang's NPI?
Dr. Matthew Chang's National Provider Identifier (NPI) is 1598949521, issued by NPPES.
Does Dr. Matthew Chang accept Medicare assignment?
Yes. Dr. Matthew Chang accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.