Kathryn Leigh Mazza, D.O.
Internal Medicine Physician · Guilford, CT
Kathryn Leigh Mazza, D.O. is an internal medicine physician with a practice address in Guilford, Connecticut, and NPI 1497196471, issued on Jul 8, 2013. Check the license (Connecticut 079272, as entered in NPPES) on the Connecticut Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Kathryn Leigh Mazza
- Credential
- D.O.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- 079272 CT
289426 NY
Self-reported in NPPES; status is on the state search - Practice location
- 1591 Boston Post RD Ste 100, Guilford, CT 06437
- Phone
- (203) 453-9911
- Enumerated
- Jul 8, 2013
- Record last updated
- Aug 19, 2025
- Fax
- (203) 458-1905
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 2,623 in Connecticut → Look up another NPI →
Also registered at 1591 Boston Post RD Ste 100
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Joseph Balsamo, M.D.Internal Medicine Physician1487650222
- Nancy Hurlburt, MDFamily Medicine Physician1952313694
- Kevin Knowlton, FNP-CFamily Nurse Practitioner1598526766
- Anthony Mascia, MDFamily Medicine Physician1306856281
- Monica Munteanu, MDInternal Medicine Physician1386643807
- Doris OkwuFamily Nurse Practitioner1679273338
Verify Kathryn Leigh Mazza in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersConnecticut Medical Examining Board
Search for license 079272Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
73% fewer Medicare Part D claims than the average internal medicine physician in 2024
853 Medicare Part D claims for 122 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D.
Most prescribed
- Atorvastatin Calcium76 claims
- Metformin Hcl56 claims
- Albuterol Sulfate Hfa52 claims
- Lisinopril52 claims
- Amlodipine Besylate37 claims
- Metoprolol Succinate37 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.
Kathryn Leigh Mazza among 2,623 internal medicine physician records in Connecticut
Kathryn Leigh Mazza, D.O. is one of 2,623 internal medicine physician records with a practice address in Connecticut. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2013, is newer than 70% of them.
- NPI issued2013 · 70% of these records are older, 28% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileNo · 63% of these records are
- Record last updated2025 · 61% 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 Connecticut practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
16 internal medicine physician records list a practice address in Guilford
They are 16 of the 504 NPPES records with a practice address in Guilford, and 2,623 internal medicine physician records in Connecticut.
All 2,623 in Connecticut → Every provider in Guilford → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Joseph Balsamo, M.D.Guilford, CT 064371487650222
- Donna Criscenzo, M.D.Guilford, CT 064371225036528
- Edward Dill, M.D.Guilford, CT 064371700886587
- Charles Glass, M.D.Guilford, CT 064371184613705
- Charles Hollander, MDGuilford, CT 064371902960529
- Jodi Indes, M.D.Guilford, CT 064371871566638
- Fraser LawrenceGuilford, CT 064371295084770
- Victor Morris, MDGuilford, CT 064371407919863
Common questions
What is Kathryn Leigh Mazza, D.O.'s NPI number?
Kathryn Leigh Mazza, D.O.'s National Provider Identifier (NPI) is 1497196471, issued on Jul 8, 2013. An NPI identifies a provider in billing; it is not a license.
Where is Kathryn Leigh Mazza, D.O. located?
The NPPES record lists a practice address at 1591 Boston Post RD Ste 100, Guilford, CT, 06437. Phone: (203) 453-9911. Providers update this record themselves, so call before visiting.
How can I verify Kathryn Leigh Mazza, D.O.'s license?
NPPES lists Connecticut license number 079272, 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 Kathryn Leigh Mazza, D.O. prescribe under Medicare Part D?
In 2024, Kathryn Leigh Mazza, D.O. had 853 Medicare Part D claims for 122 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
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.