Walter Matthew Ryan III, DO
NPI 1073503843ActiveIndividual· Internal Medicine, Allergy & Immunology· Nashua, NH
Internal Medicine, Allergy & Immunology (DO) with Mary Hitchcock Memorial Hospital, practicing in Nashua, New Hampshire. Their prescriptions cost Medicare Part D more than their services did: $122,278 for 673 claims, against $21,508 paid for services in 2024. Regeneron Healthcare Solutions, Inc. was the largest of 2 companies reporting payments in 2025, $137.22 in all, mostly food and beverage. Lists Mary Hitchcock Memorial Hospital as a hospital affiliation.
Overview
| NPI | 1073503843 |
|---|---|
| Status | Active |
| Entity type | Individual |
| Credential | DO |
| Sole proprietor | Yes |
| NPI issued | Oct 24, 2005 |
| Last updated in NPPES | Aug 4, 2023 |
| Certified by provider | Jul 19, 2023 |
Specialties and licenses
| Taxonomy | Code | License | State |
|---|---|---|---|
| Internal Medicine, Allergy & Immunology Primary | 207RA0201X | 24463 | NH |
| Allergy & Immunology | 207K00000X | OS10177 | FL |
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 - Allergy/Immunology (FL); Practitioner - Allergy/Immunology (NH) |
|---|---|
| Accepts assignment | Yes (participating) |
Medicare services in 2024
| Medicare patients | 128 |
|---|---|
| Services billed | 557 across 11 procedure codes |
| Paid by Medicare | $21,508 |
Part D prescriptions in 2024
| Prescriptions (claims) | 673 · 936 30-day fills |
|---|---|
| Patients | 137 |
| Total drug cost | $122,278 |
| Generic share | 71% of claims |
Education and affiliations
| Graduation year | 1993 |
|---|---|
| Medicare specialty | Allergy/Immunology |
Medical group
- Mary Hitchcock Memorial HospitalManchester, NH · 1,280 clinicians
Hospital affiliation
- Mary Hitchcock Memorial HospitalLebanon, NH
Industry payments (Open Payments)
- 2025$137.22 · 2 payments from 2 companies
- 2024$93.26 · 1 payment from 1 company
Top paying companies in 2025
| Company | Amount | Payments |
|---|---|---|
| Regeneron Healthcare Solutions, Inc. | $112.22 | 1 |
| Ionis Pharmaceuticals, Inc. | $25.00 | 1 |
What the 2025 payments were for
- Food and Beverage$112.22 · 1 payment
- Education$25.00 · 1 payment
Receiving payments does not imply wrongdoing. What Open Payments covers ·original records