David J. Chapman, M.D.
Gastroenterology Physician · Yorba Linda, CA
David J. Chapman, M.D. is a gastroenterology physician with a practice address in Yorba Linda, California, and NPI 1053321943, issued on Aug 9, 2006. Check the license (California G36066, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- David J. Chapman
- Credential
- M.D.
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- G36066 CA
Self-reported in NPPES; status is on the state search - Practice location
- 16671 Yorba Linda Blvd, Yorba Linda, CA 92886
- Phone
- (714) 996-3700
- Enumerated
- Aug 9, 2006
- Record last updated
- Jun 13, 2016 (not updated in 10 years: call before relying on the address or phone)
- Fax
- (714) 961-7839
- Medicare enrollment
- Enrolled (PECOS I20090317000667); accepts Medicare assignment
- Medical or professional school
- University Of California, San Francisco School Of Medicine, 1975
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
Also registered at 16671 Yorba Linda Blvd
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Keith Martin, M.D.Gastroenterology Physician1649280546
- Nancy Towbin, MDGynecology Physician1235233222
Verify David J. Chapman in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G36066Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
59% fewer Medicare Part D claims than the average gastroenterology physician in 2024
335 Medicare Part D claims for 108 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D.
Most prescribed
- Omeprazole62 claims
- Esomeprazole Magnesium53 claims
- Pantoprazole Sodium22 claims
- Creon17 claims
- Lactulose14 claims
- Famotidine13 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: $291.32
2 payments; by number, the most common kind was food and beverage; the largest payer was Janssen Biotech, Inc. The 13,350 providers of this specialty with any payment received $5,015.95 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
- Regents OF The University OF CaliforniaOrange, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
David J. Chapman among 2,140 gastroenterology physician records in California
David J. Chapman, M.D. is one of 2,140 gastroenterology physician records with a practice address in California. 83% 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 7% of them.
- NPI issued2006 · 7% of these records are older, 48% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 72% of these records are
- Graduated1975 · median 2002 among the 1,538 with a school on file
- Record last updated2016 · 60% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RG0100X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Gastroenterology Physician providers in California
There are 2,140 gastroenterology physician records in California.
All 2,140 in California → Every provider in Yorba Linda → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Tahmina Haq, M.D.Yorba Linda, CA 928861538332853
- Hyder Jamal, MDYorba Linda, CA 928861740280932
- Andrew Ko, M.D.Yorba Linda, CA 928861437170990
- Keith Martin, M.D.Yorba Linda, CA 928861649280546
- Paurush Shah, MDYorba Linda, CA 928861699090274
- Marco Paez, M.D.Corona, CA 928821902167695
- Omar Shahbaz, M.D., M.S.Corona, CA 928821417226366
- M. Mazen Jamal, M.D., M.P.H.Corona, CA 928811003916727
Common questions
What is David J. Chapman, M.D.'s NPI number?
David J. Chapman, M.D.'s National Provider Identifier (NPI) is 1053321943, issued on Aug 9, 2006. An NPI identifies a provider in billing; it is not a license.
Where is David J. Chapman, M.D. located?
The NPPES record lists a practice address at 16671 Yorba Linda Blvd, Yorba Linda, CA, 92886. Phone: (714) 996-3700. Providers update this record themselves, so call before visiting.
How can I verify David J. Chapman, M.D.'s license?
NPPES lists California license number G36066, 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 David J. Chapman, M.D. prescribe under Medicare Part D?
In 2024, David J. Chapman, M.D. had 335 Medicare Part D claims for 108 beneficiaries; the average among gastroenterology physician prescribers was 811. 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.