Marci Neilson, MD
NPI 1164652939 · Internal Medicine Physician · Rapid City, SD
Enrolled with Medicare as Practitioner - Internal Medicine · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Marci Neilson, MD is a Internal Medicine Physician provider in Rapid City, SD (NPI 1164652939).
Provider details
- NPI number
- 1164652939
- Entity type
- Individual
- Primary specialty
- Internal Medicine PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Female
- Sole proprietor
- No
- License
- 8554 (SD)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
16 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
374 Medicare services, 2024 (ranked within specialty)
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 methodology.
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) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 173 | $91 |
| Established Patient Office Or Other Outpatient Visit With Low Level OD Decision Making, If Using Time, 20 Minutes Or More99213 | 76 | $62 |
| Annual Wellness Visit, Includes a Personalized Prevention Plan of Service (pps), Subsequent VisitG0439 | 69 | $123 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 26 | $135 |
| Transitional Care Management Services for Problem of at Least Moderate Complexity99495 | 16 | $131 |
| Routine Electrocardiogram (ecg) Using at Least 12 Leads With Interpretation and Report Only |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 53 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Levothyroxine Sodium | 184 | 49 |
| Losartan Potassium | 160 | 41 |
| Atorvastatin Calcium | 127 | 38 |
| Pantoprazole Sodium | 106 | 28 |
| Amlodipine Besylate | 99 | 23 |
| Omeprazole | 95 | 30 |
| Rosuvastatin Calcium |
Practice location
Mailing address
Registry dates
- Enumerated
- 2009-07-15
- Last updated
- 2013-01-24
Frequently asked questions
- What is Marci Neilson's NPI number?
- Marci Neilson's National Provider Identifier (NPI) is 1164652939, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Marci Neilson's specialty?
- Marci Neilson is listed in the NPPES registry with a primary specialty of Internal Medicine Physician (Allopathic & Osteopathic Physicians).
- Where is Marci Neilson located?
- Marci Neilson's practice location on file with NPPES is 640 Flormann St, Rapid City, SD 57701-4679.
- What is Marci Neilson's phone number?
- The practice phone number listed in the NPPES registry for Marci Neilson is (605) 718-3300.
- Does Marci Neilson accept Medicare?
- Marci Neilson is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Marci Neilson's NPI active?
- Yes — Marci Neilson's NPI (1164652939) is active in the NPPES registry as of the last update on 2013-01-24.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.