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Gastroenterologists who accept Medicare in Fullerton, CA
CMS lists 15 clinicians in this specialty with a practice address in Fullerton. Accept Medicare assignment (the Medicare-approved amount as full payment): 15. Offer telehealth: 13.
Typical amounts Medicare approves in ZIP 92835 (2024 Medicare rates, the latest CMS has published): a new-patient visit $142, of which you pay about $36; a follow-up visit $110, of which you pay about $27 — the 20% coinsurance after the yearly Part B deductible. Clinicians who don't accept assignment can charge up to 15% more; with a Medicare Advantage plan, your plan's copay applies instead.
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Order: clinicians who accept assignment first, then by MIPS score (highest first), then by last name.
Richard E. McGuire Jr., MD
✓ Accepts Medicare assignmentMIPS score (2024): 90.3/100Graduated 1984 · New York University School of MedicineMaleDrug and device company payments (2025): $76Wanjun S. Bae, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 2002 · University of Missouri, Columbia School of MedicineMaleOther offices in Fullerton: 1Drug and device company payments (2025): $4,448Edward J. Block, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1980 · Icahn School of Medicine at Mount SinaiMaleOther offices in Fullerton: 1Drug and device company payments (2025): $4,154Elmer Y. Chang, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1998 · Northwestern University Feinberg Medical SchoolMaleDrug and device company payments (2025): $4,414Eric C. Chu, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1997 · University of California, Geffen School of MedicineMaleOther offices in Fullerton: 1Drug and device company payments (2025): $3,226Jack C. Feng, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1996 · Ohio State University College of MedicineMaleOther offices in Fullerton: 1Drug and device company payments (2025): $3,991Hyder Z. Jamal, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1990MaleOther offices in Fullerton: 3Drug and device company payments (2025): $6,458Erika Madrigal Hoyos, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 2001FemaleOther offices in Fullerton: 2Drug and device company payments (2025): $1,891Sajen J. Mathews, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1986MaleOther offices in Fullerton: 3Drug and device company payments (2025): $2,430Yee S. Miao, MD
✓ Accepts Medicare assignmentGraduated 1966MaleOther offices in Fullerton: 1Drug and device company payments (2025): $766Douglas L. Nguyen, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 2008 · Cincinnati College of Medicine and SurgeryMaleDrug and device company payments (2025): $406,320Daniald M. Rodrigues, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 2005 · Wayne State University School of MedicineMaleOther offices in Fullerton: 1Drug and device company payments (2025): $3,111Scott P. Sainburg, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1985 · University of California, Irvine, California College of MedicineMaleOther offices in Fullerton: 3Drug and device company payments (2025): $1,986Michael Santoro, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 1987 · State University of New York Downstate Medical CenterMaleDrug and device company payments (2025): $3,179Eugene J. Yoon, MD
✓ Accepts Medicare assignment✓ TelehealthGraduated 2001 · University of Virginia School of MedicineMaleOther offices in Fullerton: 3Drug and device company payments (2025): $3,464
Before you book
This list comes from Medicare's enrollment records, not from reviews. Call the office to confirm the clinician is taking new Medicare patients. With Original Medicare, a clinician who accepts assignment can only charge you the Medicare deductible and coinsurance; one who doesn't may charge up to 15% more than the Medicare-approved amount. If you have a Medicare Advantage plan, check that the clinician is in the plan's network.
The MIPS final score (0–100) comes from Medicare's Merit-based Incentive Payment System for 2024. It combines quality measures, cost, improvement activities and use of certified health records, and it sets a payment adjustment. Clinicians who report as a group share the group's score. It is not a patient rating, and many clinicians have no published score.
Payments from drug and medical device companies come from CMS Open Payments (2025 general payments: meals, travel, consulting and speaking fees, gifts and similar), summed for each clinician. Receiving payments is legal and common and does not mean a clinician did anything wrong.
Other specialists in Fullerton
- Primary care doctors271
- Nurse practitioners102
- Cardiologists37
- Dermatologists21
- Orthopedic surgeons12
- Neurologists17
- Ophthalmologists25
- Optometrists20
- Podiatrists14
- Urologists6
- Pulmonologists15
- Nephrologists6
- Endocrinologists15
- Rheumatologists9
- ENT doctors7
- Oncologists18
- Psychiatrists8
- Psychologists17
- Therapists and counselors15
- Physical therapists30
- Occupational therapists4
- Chiropractors17
- Gynecologists37
- General surgeons9
- Pain management doctors11
- Physiatrists13
- Dietitians10
- Neurosurgeons5
Other care in Fullerton
Hospitals · Nursing homes · Dialysis centers · Home health agencies · Hospices
Nearby cities
Enrollment, addresses and scores are as reported to CMS and can change. This is not a list of in-network providers for any Medicare Advantage plan, and it is not medical advice. Source: CMS Provider Data Catalog — Doctors and Clinicians National Downloadable File, Clinician MIPS Performance 2024 and Facility Affiliation Data (released Oct 2, 2026).