Marissa Blackwell, MD
NPI 1275094294ActiveIndividual· Psychiatry & Neurology, Neurology· Newark, DE
Psychiatry & Neurology, Neurology (MD) in Newark, Delaware, trained at Loyola University of Chicago, Stritch School of Medicine (class of 2019). Their prescriptions cost Medicare Part D more than their services did: $409,227 for 303 claims, against $18,712 paid for services in 2024. Catalyst Pharmaceuticals, Inc. was the largest of 3 companies reporting payments in 2025, $110.94 in all, mostly food and beverage.
Overview
| NPI | 1275094294 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Mar 31, 2019 |
| Last updated in NPPES | Jul 10, 2024 |
| Certified by provider | Jul 10, 2024 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Psychiatry & Neurology, Neurology Primary | 2084N0400X | C1-0027182 | DE |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Nov 10, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 11, 2026 | No match | — |
| New York OMIG · Nov 11, 2026 | No match | — |
| Ohio Medicaid · Nov 11, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 11, 2026 | No match | — |
| Washington HCA · Nov 11, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Neurology (DE) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 153 |
|---|---|
| Services billed | 231 across 18 procedure codes |
| Paid by Medicare | $18,712 |
Part D prescriptions in 2024
| Prescriptions (claims) | 303 · 566 30-day fills |
|---|---|
| Patients | 107 |
| Total drug cost | $409,227 |
| Generic share | 89% of claims |
Education and affiliations
| Medical school | Loyola University of Chicago, Stritch School of Medicine |
|---|---|
| Graduation year | 2019 |
| Medicare specialty | Neurology |
| Telehealth | Offers telehealth |
Medical group
- Christiana Care Health Services IncNewark, DE · 1,483 clinicians
Hospital affiliation
- Christiana HospitalNewark, DE
Other facilities
- Christianacare HomehealthHome health agency · Wilmington, DE
Industry payments (Open Payments)
- 2025$110.94 · 5 payments from 3 companies
- 2024$73.29 · 2 payments from 2 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Catalyst Pharmaceuticals, Inc. | $46.42 | 2 |
| Alnylam Pharmaceuticals Inc. | $33.05 | 1 |
| Astrazeneca Pharmaceuticals LP | $31.47 | 2 |
What the 2025 payments were for
- Food and Beverage$110.94 · 5 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All 53 neurologists in Newark · All neurologists in Delaware