Doctor profile · Federal record

Dr. Eugene Yoon, M.D.

Gastroenterology Physician (CMS: Gastroenterology) · Fullerton, CA

  • NPI 1861618449
  • Accepts Medicare
  • 25 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
1837 Sunny Crest Dr
Fullerton, CA 928353616
(714) 446-5831
fax (714) 446-7910

Credentials & registration

NPPES · NUCC
NPI registered
April 2007 — 19 yrs on file
Profile last updated
October 24, 2024
Year of graduation
2001 — 25 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State license (1)
California #A81190

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1861618449. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
936
Distinct HCPCS
10
Medicare allowed
$110,544
HCPCS Description Services Patients Avg allowed
G0500 Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito 177 176 $6
99214 Established patient office or other outpatient visit, 30-39 minutes 103 82 $137
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 92 89 $109
43235 Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope 76 75 $101
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 75 75 $254
45380 Biopsy of large bowel using a flexible endoscope 71 70 $152
99213 Established patient office or other outpatient visit, 20-29 minutes 50 43 $99
G0121 Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk 47 47 $190
45378 Diagnostic exam of large bowel using a flexible endoscope 42 42 $185
99152 Use of a drug to induce depression of consciousness by physician performing a procedure (5 years or older), initial 15 minutes 38 38 $13

In context: peer comparison

Among 3 peers in Fullerton Gastroenterology Physician, average services per provider: 60. This provider delivers 16× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$1,756
Transactions
73
Manufacturers
15
Payer (manufacturer) Industry Txns Amount
Abbvie INC. 27 $433.06
Takeda Pharmaceuticals U.S.A., INC. 8 $260.26
Genzyme Corporation 8 $195.56
Enterra Medical, INC. 1 $165.76
Gilead Sciences, INC. 4 $98.14
Pfizer INC. 4 $95.90
Ardelyx, INC. 5 $86.82
Janssen Biotech, INC. 3 $61.21
Albireo Pharma, INC. 3 $49.58
Celgene Corporation 2 $41.82
Lilly USA, LLC 2 $36.50
Phathom Pharmaceuticals, INC. 2 $33.05
Salix Pharmaceuticals, A Division of Bausch Health US, LLC 2 $31.90
Qol Medical, LLC 1 $29.65
Regeneron Healthcare Solutions, INC. 1 $25.45

By nature of payment

Food and Beverage
$1,756

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
700
Patients
199
Total drug cost
$648,048
Drug Type Claims Patients Total cost
Omeprazole Generic 212 87 $3,206
Pantoprazole Sodium Generic 83 28 $1,382
Mesalamine Generic 55 15 $33,932
Cholestyramine (Cholestyramine (With Sugar)) Brand 50 22 $5,848
Nortriptyline Hcl Generic 46 16 $650
Dicyclomine Hcl Generic 43 18 $650
Linzess (Linaclotide) Brand 34 0 $27,502
Colestipol Hcl Generic 30 13 $4,020
Creon (Lipase/Protease/Amylase) Brand 29 0 $48,214
Sucralfate Generic 24 0 $2,670

Frequently asked questions

Auto-generated from federal data
What is Dr. Eugene Yoon's medical specialty?
Dr. Eugene Yoon practices Gastroenterology Physician in Fullerton, CA.
Where does Dr. Eugene Yoon practice?
Dr. Eugene Yoon practices at 1837 Sunny Crest Dr, Fullerton, CA 928353616. Office phone: 7144465831.
What is Dr. Eugene Yoon's NPI?
Dr. Eugene Yoon's National Provider Identifier (NPI) is 1861618449, issued by NPPES.
Does Dr. Eugene Yoon accept Medicare assignment?
Yes. Dr. Eugene Yoon accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Eugene Yoon commonly perform?
Top Medicare-reported procedures in 2023: Moderate sedation services provided by the same physician or other qualified health care professional performing a gastrointestinal endoscopic service that sedation supports, requiring the presence of an independent trained observer to assist in the monito (HCPCS G0500); Established patient office or other outpatient visit (HCPCS 99214); Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (HCPCS 43239). Source: CMS Medicare Physician & Other Practitioners file.