Darren S. O'Neill, M.D.
NPI 1861434607ActiveIndividual· Internal Medicine· Enfield, CT
Internal Medicine (M.D.) in Enfield, Connecticut, trained at University of Connecticut School of Medicine (class of 1994). Their prescriptions cost Medicare Part D more than their services did: $1,829,327 for 18,970 claims, against $321,565 paid for services in 2024. Pfizer Inc. reported $22.48 in payments in 2025, mostly food and beverage.
Overview
| NPI | 1861434607 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | M.D. |
| Sole proprietor | No |
| NPI issued | Jun 12, 2006 |
| Last updated in NPPES | May 19, 2026 |
| Certified by provider | May 19, 2026 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine Primary | 207R00000X | 36429 | CT |
| Internal Medicine | 207R00000X | 151285 | MA |
Exclusion screening
| List | Result | Details |
|---|---|---|
| HHS-OIG LEIE · Oct 9, 2026 | No match | Checked by NPI and by name + state |
| North Carolina Medicaid · Nov 4, 2026 | No match | — |
| New York OMIG · Nov 4, 2026 | No match | — |
| Ohio Medicaid · Nov 4, 2026 | No match | — |
| Pennsylvania Medicheck · Nov 4, 2026 | No match | — |
| Washington HCA · Nov 4, 2026 | No match | — |
Official OIG search · How matching works ·Bulk check a roster
Medicare
| Enrollment (PECOS) | Enrolled Practitioner - Internal Medicine (CT); Practitioner - Internal Medicine (MA) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 746 |
|---|---|
| Services billed | 4,776 across 50 procedure codes |
| Paid by Medicare | $321,565 |
Part D prescriptions in 2024
| Prescriptions (claims) | 18,970 · 39,653 30-day fills |
|---|---|
| Patients | 1,268 |
| Total drug cost | $1,829,327 |
| Generic share | 88% of claims |
Education and affiliations
| Medical school | University of Connecticut School of Medicine |
|---|---|
| Graduation year | 1994 |
| Medicare specialty | Internal Medicine |
| Telehealth | Offers telehealth |
Medical groups
- Baystate Medical Practices IncSpringfield, MA · 1,369 clinicians
- Springfield Medical Associates, Inc.Enfield, CT · 10 clinicians
Hospital affiliations
- Baystate Medical CenterSpringfield, MA
- Baystate Noble HospitalWestfield, MA
- Baystate Wing HospitalPalmer, MA
- Johnson Memorial HospitalStafford Springs, CT
- Mercy Medical CtrSpringfield, MA
Other facilities
- Amedisys Home Health CareHome health agency · Agawam, MA
- Baystate Home HealthHome health agency · W Springfield, MA
- Elara CaringHome health agency · Rocky Hill, CT
- Elara CaringHome health agency · Braintree, MA
- Encompass Health Home HealthHome health agency · Ludlow, MA
Industry payments (Open Payments)
- 2025$22.48 · 1 payment from 1 company
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Pfizer Inc. | $22.48 | 1 |
What the 2025 payments were for
- Food and Beverage$22.48 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records
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