Walter Matthew Ryan, DO
Allergy & Immunology (Internal Medicine) Physician · Nashua, NH
Walter Matthew Ryan, DO is an allergy & immunology (internal medicine) physician with a practice address in Nashua, New Hampshire, and NPI 1073503843, issued on Oct 24, 2005. Check the license (New Hampshire 24463, as entered in NPPES) on the New Hampshire Board of Medicine; the Medicare figures below come from public CMS files.
- Name
- Walter Matthew Ryan
- Credential
- DO
- Primary taxonomy
- Allergy & Immunology (Internal Medicine) Physician 207RA0201X
- License numbers
- 24463 NH
OS10177 FL
Self-reported in NPPES; status is on the state search - Practice location
- 2300 Southwood Dr, Nashua, NH 03063
- Phone
- (603) 577-4000
- Enumerated
- Oct 24, 2005
- Record last updated
- Aug 4, 2023
- Medicaid ID
- 279624400 FL
- Medicare enrollment
- Enrolled (PECOS I20230828000909); accepts Medicare assignment
- Entity
- Type 1 · individual
1 nearest allergy & immunology (internal medicine) physician record → All 2 in New Hampshire → Look up another NPI →
Also registered at 2300 Southwood Dr
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Susan Abel, M.D.Pediatrics Physician1093826893
- Paul Acevedo, CNPNurse Practitioner1184198590
- Asma Ahmed, MDInternal Medicine Physician1972788073
- May Aldaabil, M.DRheumatology Physician1306243910
Verify Walter Matthew Ryan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersNew Hampshire Board of Medicine
Search for license 24463Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
15% fewer Medicare Part D claims than the average allergy & immunology (internal medicine) physician in 2024
673 Medicare Part D claims for 137 beneficiaries, against an average of 789 among the 429 providers of this specialty who prescribed in Part D. Brand-name drugs were 29% of claims.
Most prescribed
- Levocetirizine Dihydrochloride96 claims
- Azelastine Hcl80 claims
- Fluticasone Propionate65 claims
- Ipratropium Bromide59 claims
- Albuterol Sulfate Hfa37 claims
- Wixela Inhub37 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The practice group's MIPS final score for 2023 (Medicare payment program): 69.4 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $93.26
1 payment: food and beverage; the largest payer was AstraZeneca Pharmaceuticals LP. The 321 providers of this specialty with any payment received $7,456.30 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
One hospital affiliation
- Mary Hitchcock Memorial HospitalNashua, NH · Acute Care Hospitals3 of 5 stars
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through); hospitals matched to CMS Hospital General Information (Care Compare) (data.cms.gov). Star ratings are CMS hospital ratings, not ratings of this provider.
Allergy & Immunology (Internal Medicine) Physician providers in New Hampshire
There are 2 allergy & immunology (internal medicine) physician records in New Hampshire.
All 2 in New Hampshire → Every provider in Nashua → Allergy & Immunology (Internal Medicine) Physician nationwide →
The 1 allergy & immunology (internal medicine) physician record with the nearest ZIP codes
- Martha Elias, MDLebanon, NH 037561427062405
Common questions
What is Walter Matthew Ryan, DO's NPI number?
Walter Matthew Ryan, DO's National Provider Identifier (NPI) is 1073503843, issued on Oct 24, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Walter Matthew Ryan, DO located?
The NPPES record lists a practice address at 2300 Southwood Dr, Nashua, NH, 03063. Phone: (603) 577-4000. Providers update this record themselves, so call before visiting.
How can I verify Walter Matthew Ryan, DO's license?
NPPES lists New Hampshire license number 24463, as entered by the provider. Search the New Hampshire Board of Medicine at https://www.oplc.nh.gov/board-medicine. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Walter Matthew Ryan, DO prescribe under Medicare Part D?
In 2024, Walter Matthew Ryan, DO had 673 Medicare Part D claims for 137 beneficiaries; the average among allergy & immunology (internal medicine) physician prescribers was 789. Part D covers Medicare prescriptions only.
What is Walter Matthew Ryan, DO's MIPS final score?
The 2023 MIPS final score is 69.4 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.