Cassandra Williams, MD
NPI 1558546820ActiveIndividual· Internal Medicine· Amherst, NY
Internal Medicine (MD) with Cogent Medical Care PC and 1 other group, practicing in Amherst, New York. Their prescriptions cost Medicare Part D more than their services did: $3,261,495 for 23,198 claims, against $69,568 paid for services in 2024. Cook Medical LLC was the largest of 2 companies reporting payments in 2025, $348.78 in all, mostly food and beverage. Lists Erie County Medical Center and 1 other hospital as hospital affiliations.
Overview
| NPI | 1558546820 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Jan 7, 2008 |
| Last updated in NPPES | Oct 30, 2020 |
| Certified by provider | Oct 30, 2020 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | 302772 | NY |
| Internal Medicine | 207R00000X | 200800022 | NC |
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 - Internal Medicine (NC); Practitioner - Internal Medicine (NY) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 206 |
|---|---|
| Services billed | 826 across 10 procedure codes |
| Paid by Medicare | $69,568 |
Part D prescriptions in 2024
| Prescriptions (claims) | 23,198 · 23,262 30-day fills |
|---|---|
| Patients | 441 |
| Total drug cost | $3,261,495 |
| Generic share | 73% of claims |
Education and affiliations
| Graduation year | 2005 |
|---|---|
| Medicare specialty | Internal Medicine |
Medical groups
- Cogent Medical Care PCBuffalo, NY · 154 clinicians
- Maine Medical Consultants PCBuffalo, NY · 51 clinicians
Hospital affiliations
- Erie County Medical CenterBuffalo, NY
- Mercy Hospital of BuffaloBuffalo, NY
Other facilities
- Hospice Buffalo IncHospice · Cheektowaga, NY
- Terrace View Long Term Care FacilityNursing home · Buffalo, NY
Industry payments (Open Payments)
- 2025$348.78 · 3 payments from 2 companies
- 2024$231.88 · 2 payments from 2 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Cook Medical LLC | $223.79 | 2 |
| Otsuka America Pharmaceutical, Inc. | $124.99 | 1 |
What the 2025 payments were for
- Food and Beverage$348.78 · 3 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All 43 internal medicine physicians in Amherst · All internal medicine physicians in New York