Quick answers
- Does Ethan-Quan H. Nguyen accept Medicare assignment?
- Yes. Medicare's clinician data says Ethan-Quan H. Nguyen accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Ethan-Quan H. Nguyen see?
- In 2024, CMS data shows 394 Original Medicare patients and 2,728 services for Ethan-Quan H. Nguyen. This counts Original Medicare only and measures volume, not quality.
- What is Ethan-Quan H. Nguyen's NPI number?
- 1104828508. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Ethan-Quan H. Nguyen, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 394 |
|---|---|
| Services billed to Medicare | 2,728 |
| Different services or procedures | 61 |
| Participating Medicare provider | Yes |
| Average age of these patients | 77 |
Most frequent services
- Destruction of precancer skin growth, 2-14 growths (17003)677 services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)647 services
- Pathology examination of tissue using a microscope, intermediate complexity (88305)231 services
- Biopsy of related skin growth, first growth (11102)136 services
- Destruction of precancer skin growth, 1 growth (17000)131 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Arthritis47%
- Chronic kidney disease31%
- Diabetes30%
- Ischemic heart disease30%
Practice locations
Addresses where Ethan-Quan H. Nguyen is enrolled with Medicare (CMS data updated October 2, 2026).
- 4336 Market StRiverside, CA 92501 (951) 682‑9293
Specialties
- Dermatologyprimary
Other dermatologists in Riverside
Clinicians with the same Medicare primary specialty in Riverside, CA — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Georgetown University School Of Medicine |
| Graduation year | 1991 (35 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1104828508 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians