Registry data as of Aug 27, 2026

Gregory D'Onofrio, M.D.

Cardiovascular Disease Physician · Stamford, CT

Gregory D'Onofrio, M.D. is a cardiovascular disease physician with a practice address in Stamford, Connecticut, and NPI 1255304796, issued on Feb 7, 2006. Check the license (Connecticut 149608, as entered in NPPES) on the Connecticut Medical Examining Board; the Medicare figures below come from public CMS files.

Record from CMS NPPES, loaded Aug 27, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordas of Aug 27, 2026
1255304796
Name
Gregory D'Onofrio
Credential
M.D.
Primary taxonomy
Cardiovascular Disease Physician 207RC0000X
License number
149608 CT
Self-reported in NPPES; status is on the state search
Practice location
29 Hospital Plaza, Stamford, CT 06902
Phone
(203) 348-7410
Enumerated
Feb 7, 2006
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). A record is not a license: verify it with the state board.
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Also registered at 29 Hospital Plaza

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Sarah Buckingham, MDNeurology Physician1447549639
  2. Salvatore Carbonaro, M.D.Cardiovascular Disease Physician1821141805
  3. Joonun Choi, MDCardiovascular Disease Physician1053583914
  4. Kathryn CreaghAdult Health Nurse Practitioner1588088355
  5. Evelyn Cusack, M.D.Cardiovascular Disease Physician1700874435
  6. Marissa Defreese, MDSurgery Physician1194963462

Verify Gregory D'Onofrio in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersConnecticut Medical Examining Board
    Search for license 149608
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS, AOA, NCCPA, AANPNot checked
Open the Connecticut license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

27% fewer Medicare Part D claims than the average cardiovascular disease physician in 2024

2,288 Medicare Part D claims for 296 beneficiaries, against an average of 3,149 among the 19,556 providers of this specialty who prescribed in Part D. Brand-name drugs were 14% of claims.

  1. Gregory D'Onofrio2,288
  2. Specialty average3,149

Most prescribed

  1. Metoprolol Succinate247 claims
  2. Amlodipine Besylate199 claims
  3. Atorvastatin Calcium193 claims
  4. Eliquis155 claims
  5. Losartan Potassium127 claims
  6. Furosemide123 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 Medicare quality score for 2023: 79.1 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.

  1. Qualityout of 100 · 30% of the final score73.2
  2. Costout of 100 · 30%57.9
  3. Promoting interoperabilityout of 100 · 25%99.0
  4. Improvement activities40 of 40 points · 15%100.0

Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).

One hospital or facility affiliation

  1. Stamford Health Medical Group IncStamford, CT

Source: CMS Doctors and Clinicians affiliations; Hospital General Information (Care Compare) (data.cms.gov). Star ratings are CMS hospital ratings, not ratings of this provider.

Cardiovascular Disease Physician providers in Connecticut

There are 444 cardiovascular disease physician records in Connecticut.

Other cardiovascular disease physician records in Connecticut

  1. Khaled AbazaMiddletown, CT1255986121
  2. Binny Abraham, M.D.New Haven, CT1760657647
  3. Joseph Abreu, MDTorrington, CT1003996240
  4. Sneha Agarwalla, MDBloomfield, CT1801245162
  5. Elliot Agin, M.D.Milford, CT1790729093
  6. Keshava Aithal, MDMiddletown, CT1811005713
  7. Emmanuel AkintoyeNew Haven, CT1659767598
  8. Abeera Akram, MDWaterbury, CT1497240238
  9. Mohammed Al-Damluji, MD, MPHMiddletown, CT1114312766
  10. Karl Alcan, M.D.Trumbull, CT1689778144

Common questions

What is Gregory D'Onofrio, M.D.'s NPI number?

Gregory D'Onofrio, M.D.'s National Provider Identifier (NPI) is 1255304796, issued on Feb 7, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Gregory D'Onofrio, M.D. located?

The NPPES record lists a practice address at 29 Hospital Plaza, Stamford, CT, 06902. Phone: (203) 348-7410. Providers update this record themselves, so call before visiting.

How can I verify Gregory D'Onofrio, M.D.'s license?

NPPES lists Connecticut license number 149608, as entered by the provider. Search the Connecticut Medical Examining Board at https://www.elicense.ct.gov/Lookup/LicenseLookup.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Gregory D'Onofrio, M.D. prescribe under Medicare Part D?

In 2024, Gregory D'Onofrio, M.D. had 2,288 Medicare Part D claims for 296 beneficiaries; the average among cardiovascular disease physician prescribers was 3,149. Part D covers Medicare prescriptions only.

What is Gregory D'Onofrio, M.D.'s Medicare quality score?

The 2023 MIPS final score is 79.1 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), loaded Aug 27, 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.

Every figure on PlainDoctor is rendered directly from the federal CMS NPPES registry, Medicare Part D, MIPS, and Open Payments records, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 27, 2026.