Brian O'Leary, MD
NPI 1295702439ActiveIndividual· Internal Medicine· Naperville, IL
Internal Medicine (MD) in Naperville, Illinois, trained at Northwestern University Feinberg Medical School (class of 1985). Their prescriptions cost Medicare Part D more than their services did: $1,250,507 for 11,344 claims, against $46,323 paid for services in 2024. Novo Nordisk Inc was the largest of 9 companies reporting payments in 2025, $322.41 in all, mostly food and beverage.
Overview
| NPI | 1295702439 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | MD |
| Sole proprietor | No |
| NPI issued | Mar 7, 2006 |
| Last updated in NPPES | Sep 24, 2021 |
| Certified by provider | Sep 24, 2021 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | 036073069 | IL |
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 (IL) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 136 |
|---|---|
| Services billed | 1,325 across 65 procedure codes |
| Paid by Medicare | $46,323 |
Part D prescriptions in 2024
| Prescriptions (claims) | 11,344 · 25,980 30-day fills |
|---|---|
| Patients | 591 |
| Total drug cost | $1,250,507 |
| Generic share | 87% of claims |
Education and affiliations
| Medical school | Northwestern University Feinberg Medical School |
|---|---|
| Graduation year | 1985 |
| Medicare specialty | Internal Medicine |
| Telehealth | Offers telehealth |
Medical groups
- Dupage Medical Group LtdWinfield, IL · 1,322 clinicians
- Rci (Wrs) LLCOak Park, IL · 360 clinicians
Hospital affiliation
- Edward HospitalNaperville, IL
Other facilities
- Residential Home HealthHome health agency · Lisle, IL
- Lightways Hospice and Serious Illness CareHospice · Joliet, IL
Industry payments (Open Payments)
- 2025$322.41 · 16 payments from 9 companies
- 2024$405.39 · 22 payments from 9 companies
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Novo Nordisk Inc | $70.16 | 4 |
| Lilly USA, LLC | $60.73 | 3 |
| Sanara Medtech Inc. | $58.24 | 2 |
| Sumitomo Pharma America, Inc. | $43.38 | 2 |
| Boehringer Ingelheim Pharmaceuticals, Inc. | $21.82 | 1 |
What the 2025 payments were for
- Food and Beverage$322.41 · 16 payments
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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All 114 internal medicine physicians in Naperville · All internal medicine physicians in Illinois