Eugene Jay Yoon, M.D.
Gastroenterology Physician · Fullerton, CA
Eugene Jay Yoon, M.D. is a gastroenterology physician with a practice address in Fullerton, California, and NPI 1861618449, issued on Apr 18, 2007. Check the license (California A81190, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Eugene Jay Yoon
- Credential
- M.D.
- Primary taxonomy
- Gastroenterology Physician 207RG0100X
- License number
- A81190 CA
Self-reported in NPPES; status is on the state search - Practice location
- 1837 Sunny Crest Dr, Fullerton, CA 92835
- Phone
- (714) 446-5831
- Enumerated
- Apr 18, 2007
- Record last updated
- Oct 24, 2024
- Fax
- (714) 446-7910
- Medicare enrollment
- Enrolled (PECOS I20071018000670); accepts Medicare assignment
- Medical or professional school
- University Of Virginia School Of Medicine, 2001
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest gastroenterology physician records → All 2,140 in California → Look up another NPI →
Also registered at 1837 Sunny Crest Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Martin Carr, M.D.Gastroenterology Physician1326034265
- Maica Javien, NP-CFamily Nurse Practitioner1255086443
- Patrick Koo, MDGastroenterology Physician1801152772
- Thu Le, FNPFamily Nurse Practitioner1033698915
- Erica Lee, NPFamily Nurse Practitioner1013506740
- Sajen Mathews, MDGastroenterology Physician1326048323
Verify Eugene Jay Yoon in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license A81190Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
34% more Medicare Part D claims than the average gastroenterology physician in 2024
1,086 Medicare Part D claims for 284 beneficiaries, against an average of 811 among the 16,445 providers of this specialty who prescribed in Part D. Brand-name drugs were 17% of claims. 27 claims were for opioids.
Most prescribed
- Omeprazole215 claims
- Nortriptyline Hcl93 claims
- Pantoprazole Sodium57 claims
- Mesalamine54 claims
- Dicyclomine Hcl40 claims
- Colestipol Hcl31 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: $1,756.18
78 payments; by number, the most common kind was food and beverage; the largest payer was Abbvie 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
- Providence Medical FoundationFullerton, CA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Eugene Jay Yoon among 2,140 gastroenterology physician records in California
Eugene Jay Yoon, 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 2007, is newer than 52% of them.
- NPI issued2007 · 52% of these records are older, 37% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 72% of these records are
- Graduated2001 · median 2002 among the 1,538 with a school on file
- Record last updated2024 · 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 Fullerton → Gastroenterology Physician nationwide →
The 8 gastroenterology physician records with the nearest ZIP codes
- Martin Carr, M.D.Fullerton, CA 928351326034265
- Patrick Koo, MDFullerton, CA 928351801152772
- Sajen Mathews, MDFullerton, CA 928351326048323
- Yeeshun Miao, M.D.Fullerton, CA 928351518953983
- Kumkum Patel, M.D., MPHFullerton, CA 928351003178138
- Vijay Prabhakar, M.D.Fullerton, CA 928351932593167
- Scott Sainburg, M.D.Fullerton, CA 928351184610552
- Richard McGuire, M.D.Fullerton, CA 928321437196730
Common questions
What is Eugene Jay Yoon, M.D.'s NPI number?
Eugene Jay Yoon, M.D.'s National Provider Identifier (NPI) is 1861618449, issued on Apr 18, 2007. An NPI identifies a provider in billing; it is not a license.
Where is Eugene Jay Yoon, M.D. located?
The NPPES record lists a practice address at 1837 Sunny Crest Dr, Fullerton, CA, 92835. Phone: (714) 446-5831. Providers update this record themselves, so call before visiting.
How can I verify Eugene Jay Yoon, M.D.'s license?
NPPES lists California license number A81190, 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 Eugene Jay Yoon, M.D. prescribe under Medicare Part D?
In 2024, Eugene Jay Yoon, M.D. had 1,086 Medicare Part D claims for 284 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.