Doctor profile · Federal record

Dr. Chun Ouyang, M.D., PH.D.

Internal Medicine Physician (CMS: Gastroenterology) · Walnut Creek, CA

  • NPI 1336115328
  • Accepts Medicare
  • 34 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
1425 S Main St, Kaiser Foundation Hospital, GI Division
Walnut Creek, CA 945965318
(925) 295-4020

Credentials & registration

NPPES · NUCC
NPI registered
February 2006 — 20 yrs on file
Profile last updated
December 13, 2021
Year of graduation
1992 — 34 yrs since
Specialty taxonomy
207R00000X — NUCC code
State license (1)
Massachusetts #217077

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1336115328. Last verified May 11, 2026.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$22
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
CapsoVision, INC. 1 $21.57

By nature of payment

Food and Beverage
$22

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
905
Patients
628
Total drug cost
$200,272
Drug Type Claims Patients Total cost
Gavilyte-C (Peg3350/Sod Sulf,Bicarb,Cl/Kcl) Brand 563 559 $11,845
Entecavir Generic 39 11 $2,485
Pantoprazole Sodium Generic 32 19 $1,007
Omeprazole Generic 28 14 $302
Cholestyramine (Cholestyramine (With Sugar)) Brand 26 14 $1,296
Esomeprazole Magnesium Generic 26 11 $521
Tenofovir Disoproxil Fumarate Generic 26 0 $1,478
Famotidine Generic 25 0 $347
Lactulose Generic 25 0 $885
Budesonide Dr (Budesonide) Brand 23 0 $1,774

Frequently asked questions

Auto-generated from federal data
What is Dr. Chun Ouyang's medical specialty?
Dr. Chun Ouyang practices Internal Medicine Physician in Walnut Creek, CA.
Where does Dr. Chun Ouyang practice?
Dr. Chun Ouyang practices at 1425 S Main St, Walnut Creek, CA 945965318. Office phone: 9252954020.
What is Dr. Chun Ouyang's NPI?
Dr. Chun Ouyang's National Provider Identifier (NPI) is 1336115328, issued by NPPES.
Does Dr. Chun Ouyang accept Medicare assignment?
Yes. Dr. Chun Ouyang accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.