Mark Vanviegen, ENP/FNP-BC
NPI 1477541779 · Nurse Practitioner · Buffalo, NY
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Provider details
- NPI number
- 1477541779
- Entity type
- Individual
- Primary specialty
- Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Credential
- ENP/FNP-BC
- Sex
- Male
- Sole proprietor
- No
- License
- 149084 (NC)
Specialties & taxonomies
Physician Assistants & Advanced Practice Nursing Providers
Physician Assistants & Advanced Practice Nursing Providers
Physician Assistants & Advanced Practice Nursing Providers
Physician Assistants & Advanced Practice Nursing Providers
Physician Assistants & Advanced Practice Nursing Providers
- Nurse Practitioner363L00000X
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 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
234 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) |
|---|---|---|
| Emergency Department Visit With High Level of Medical Decision Making99285 | 115 | $158 |
| Emergency Department Visit With Moderate Level of Medical Decision Making99284 | 108 | $108 |
| Emergency Department Visit With Low Level of Medical Decision Making99283 | 11 | $66 |
Typical Medicare-allowed amounts for these services range $66–$158 (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 · 8 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Cephalexin | 38 | 38 |
| Oxycodone Hcl/Acetaminophenbrand: Oxycodone-Acetaminophen | 29 | 29 |
| Diclofenac Sodium | 26 | 26 |
| Ondansetron Hcl | 18 | 18 |
| Amoxicillin/Potassium Clavbrand: Amoxicillin-Clavulanate Potass | 14 | 14 |
| Dexamethasone | 13 | 13 |
| Albuterol Sulfatebrand: Albuterol Sulfate Hfa | 11 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$30 across 1 record (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
- 2005-10-11
- Last updated
- 2026-06-04
- Certified
- 2026-06-04
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.