Registry data as of Aug 27, 2026

Marcus Mayus, M.D.

Internal Medicine Physician · Greenwich, CT

Marcus Mayus, M.D. is an internal medicine physician with a practice address in Greenwich, Connecticut, and NPI 1073734935, issued on May 1, 2007. Check the license (Connecticut 045877, 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
1073734935
Name
Marcus Mayus
Credential
M.D.
Primary taxonomy
Internal Medicine Physician 207R00000X
License number
045877 CT
Self-reported in NPPES; status is on the state search
Practice location
81 Holly Hill LN FL 3, Greenwich, CT 06830
Phone
(203) 869-5515
Enumerated
May 1, 2007
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 81 Holly Hill LN FL 3

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

  1. Timothy Brandriff, PAPhysician Assistant1740320092
  2. Glenn Gandelman, MDSpecialist1033117437

Verify Marcus Mayus in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersConnecticut Medical Examining Board
    Search for license 045877
    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.

6.2 times the Medicare Part D claims of the average internal medicine physician in 2024

17,140 Medicare Part D claims for 1,459 beneficiaries, against an average of 2,785 among the 127,794 providers of this specialty who prescribed in Part D. Brand-name drugs were 11% of claims. 177 claims were for opioids.

  1. Marcus Mayus17,140
  2. Specialty average2,785

Most prescribed

  1. Levothyroxine Sodium927 claims
  2. Rosuvastatin Calcium837 claims
  3. Atorvastatin Calcium836 claims
  4. Losartan Potassium543 claims
  5. Amlodipine Besylate518 claims
  6. Pantoprazole Sodium476 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 Medicare quality score for 2023: 94.2 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.

  1. Qualityout of 100 · 30% of the final score81.9
  2. Costout of 100 · 30%
  3. Promoting interoperabilityout of 100 · 25%99.4
  4. Improvement activities40 of 40 points · 15%100.0

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

Industry payments in 2024: $5,375.46

243 payments, mostly food and beverage; the largest payer was Abbvie Inc.. The 65,274 providers of this specialty with any payment received $2,536.66 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Marcus Mayus$5,375.46
  2. Specialty average$2,536.66

Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.

One hospital or facility affiliation

  1. Marcus Mayus MD IncGreenwich, 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.

55 internal medicine physician records list a Greenwich practice address

They are 55 of the 1,184 NPPES records with a Greenwich practice address, and 2,830 internal medicine physician records in Connecticut.

Other internal medicine physician records in Connecticut

  1. Christina AbavanaBridgeport, CT1508206574
  2. Hoda Abdel Salam, M.D.New Britain, CT1144509316
  3. Gada Abdelhafiz, MDNew London, CT1467649558
  4. Mahmoud Abdelrahman, MDBridgeport, CT1467072868
  5. Simon Abi-SalehBridgeport, CT1891315529
  6. Gerard Abidor, D.O.Bridgeport, CT1518014539
  7. Richard Abraham, M.D.Canton, CT1023044252
  8. Odaliz Abreu-Lanfranco, MDNew Haven, CT1538276134
  9. Nila Aburto, MDStamford, CT1396325718
  10. Angelo Accomando, M.D.East Haven, CT1063454247

Common questions

What is Marcus Mayus, M.D.'s NPI number?

Marcus Mayus, M.D.'s National Provider Identifier (NPI) is 1073734935, issued on May 1, 2007. An NPI identifies a provider in billing; it is not a license.

Where is Marcus Mayus, M.D. located?

The NPPES record lists a practice address at 81 Holly Hill LN FL 3, Greenwich, CT, 06830. Phone: (203) 869-5515. Providers update this record themselves, so call before visiting.

How can I verify Marcus Mayus, M.D.'s license?

NPPES lists Connecticut license number 045877, 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 Marcus Mayus, M.D. prescribe under Medicare Part D?

In 2024, Marcus Mayus, M.D. had 17,140 Medicare Part D claims for 1,459 beneficiaries; the average among internal medicine physician prescribers was 2,785. Part D covers Medicare prescriptions only.

What is Marcus Mayus, M.D.'s Medicare quality score?

The 2023 MIPS final score is 94.2 of 100. 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.