Daniel O'Leary, M.D.
Internal Medicine Physician · Leominster, MA
Daniel O'Leary, M.D. is an internal medicine physician with a practice address in Leominster, Massachusetts, and NPI 1447346531, issued on Oct 5, 2006. Check the license (Massachusetts 57335, as entered in NPPES) on the Massachusetts Board of Registration in Medicine; the Medicare figures below come from public CMS files.
- Name
- Daniel O'Leary
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 57335 MA
Self-reported in NPPES; status is on the state search - Practice location
- 50 Memorial Drive, Leominster, MA 01453
- Phone
- (978) 534-4241
- Enumerated
- Oct 5, 2006
- Record last updated
- Feb 28, 2013 (not updated in 13 years: call before relying on the address or phone)
- Fax
- (978) 534-3705
- Medicaid ID
- 3031683 MA
- Medicare enrollment
- Enrolled (PECOS I20050405001141); accepts Medicare assignment
- Medical or professional school
- University Of Massachusetts Medical School, 1985
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 6,825 in Massachusetts → Look up another NPI →
Also registered at 50 Memorial Drive
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Daniel O'Leary in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMassachusetts Board of Registration in Medicine
Search for license 57335Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
5.1 times the Medicare Part D claims of the average internal medicine physician in 2024
16,274 Medicare Part D claims for 1,239 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 9% of claims. 341 claims were for opioids.
Most prescribed
- Atorvastatin Calcium954 claims
- Amlodipine Besylate794 claims
- Lisinopril762 claims
- Losartan Potassium761 claims
- Levothyroxine Sodium759 claims
- Simvastatin540 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 MIPS final score for 2023 (Medicare payment program): 97 of 100
The Merit-based Incentive Payment System score is reported for this clinician. 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; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Leominster Medical AssociatesLeominster, MA
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Daniel O'Leary among 6,825 internal medicine physician records in Massachusetts
Daniel O'Leary, M.D. is one of 6,825 internal medicine physician records with a practice address in Massachusetts. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 12% of them.
- NPI issued2006 · 12% of these records are older, 54% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileYes · 60% of these records are
- Graduated1985 · median 2004 among the 4,103 with a school on file
- Record last updated2013 · 64% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Massachusetts practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
35 internal medicine physician records list a practice address in Leominster
They are 35 of the 1,151 NPPES records with a practice address in Leominster, and 6,825 internal medicine physician records in Massachusetts.
All 6,825 in Massachusetts → Every provider in Leominster → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Glenn Allison, M.D.Leominster, MA 014531497745848
- Stephen Child, M.D.Leominster, MA 014531790747442
- Kimberly Ebb, MDLeominster, MA 014531790777589
- Ashraf Elkerm, MDLeominster, MA 014531306825831
- Mark Hryniewich, MDLeominster, MA 014531255307781
- Myria Munoz, MDLeominster, MA 014531942261987
- Jyoti Nagarkar, MDLeominster, MA 014531013903210
- Binu Pathrose, MDLeominster, MA 014531023096682
Common questions
What is Daniel O'Leary, M.D.'s NPI number?
Daniel O'Leary, M.D.'s National Provider Identifier (NPI) is 1447346531, issued on Oct 5, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Daniel O'Leary, M.D. located?
The NPPES record lists a practice address at 50 Memorial Drive, Leominster, MA, 01453. Phone: (978) 534-4241. Providers update this record themselves, so call before visiting.
How can I verify Daniel O'Leary, M.D.'s license?
NPPES lists Massachusetts license number 57335, as entered by the provider. Search the Massachusetts Board of Registration in Medicine at https://findmydoctor.mass.gov/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Daniel O'Leary, M.D. prescribe under Medicare Part D?
In 2024, Daniel O'Leary, M.D. had 16,274 Medicare Part D claims for 1,239 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
What is Daniel O'Leary, M.D.'s MIPS final score?
The 2023 MIPS final score is 97 of 100. 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.