Eun Byun, MD
NPI 1861683047 · Specialist · Fountain Valley, CA
Enrolled with Medicare as Practitioner - Physical Medicine and Rehabilitation · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Eun Byun, MD is a Specialist provider in Fountain Valley, CA (NPI 1861683047).
Provider details
- NPI number
- 1861683047
- Entity type
- Individual
- Primary specialty
- SpecialistOther Service Providers
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- 25MA09225700 (NJ)
Specialties & taxonomies
Other Service Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
18 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
4,887 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Subsequent Nursing Facility Care With Moderate Level of Medical Decision Making, Per Day, If Using Time, at Least 30 Minutes99309 | 2,794 | $113 |
| Subsequent Nursing Facility Care With Straightforward Level of Medical Decision Making, Per Day, If Using Time, 20 Minutes Or More99308 | 1,803 | $78 |
| Initial Nursing Facility Care With High Level of Medical Decision Making, Per Day, If Using Time, 50 Minutes Or More99306 | 246 | $189 |
| Initial Nursing Facility Care With Moderate Level of Medical Decision Making, Per Day, If Using Time, at Least 35 Minutes99305 | 44 | $139 |
Typical Medicare-allowed amounts for these services range $78–$189 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 11 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Hydrocodone/Acetaminophenbrand: Hydrocodone-Acetaminophen | 120 | 32 |
| Tramadol Hcl | 99 | 28 |
| Gabapentin | 61 | 19 |
| Pregabalin | 59 | 18 |
| Baclofen | 48 | — |
| Oxycodone Hcl/Acetaminophenbrand: Oxycodone-Acetaminophen | 41 | 13 |
| Oxycodone Hcl |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$9,103 across 32 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-08-05
- Last updated
- 2017-01-12
Frequently asked questions
- What is Eun Byun's NPI number?
- Eun Byun's National Provider Identifier (NPI) is 1861683047, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Eun Byun's specialty?
- Eun Byun is listed in the NPPES registry with a primary specialty of Specialist (Other Service Providers).
- Where is Eun Byun located?
- Eun Byun's practice location on file with NPPES is 10419 Slater Ave Apt 107, Fountain Valley, CA 92708-7704.
- What is Eun Byun's phone number?
- The practice phone number listed in the NPPES registry for Eun Byun is (646) 717-2533.
- Does Eun Byun accept Medicare?
- Eun Byun is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Eun Byun's NPI active?
- Yes — Eun Byun's NPI (1861683047) is active in the NPPES registry as of the last update on 2017-01-12.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.