Antonios Katsigiannis, M.D.
Internal Medicine Physician · Stamford, CT
Antonios Katsigiannis, M.D. is an internal medicine physician with a practice address in Stamford, Connecticut, and NPI 1629157276, issued on Nov 3, 2006. Check the license (Connecticut 035140, as entered in NPPES) on the Connecticut Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Antonios Katsigiannis
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 035140 CT
Self-reported in NPPES; status is on the state search - Practice location
- 90 Morgan St, Stamford, CT 06905
- Phone
- (203) 323-8437
- Enumerated
- Nov 3, 2006
- Record last updated
- Oct 21, 2019 (not updated in 7 years: call before relying on the address or phone)
- Fax
- (203) 327-4628
- Medicare enrollment
- Enrolled (PECOS I20081014000319); accepts Medicare assignment
- Medical or professional school
- New York Medical College, 1993
- Entity
- Type 1 · individual
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Verify Antonios Katsigiannis in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersConnecticut Medical Examining Board
Search for license 035140Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
10% more Medicare Part D claims than the average internal medicine physician in 2024
3,509 Medicare Part D claims for 165 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 16% of claims. 142 claims were for opioids.
Most prescribed
- Rosuvastatin Calcium246 claims
- Amlodipine Besylate150 claims
- Atorvastatin Calcium137 claims
- Levothyroxine Sodium120 claims
- Alprazolam108 claims
- Pantoprazole Sodium104 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.
Industry payments in 2024: $3,280.54
120 payments; by number, the most common kind was food and beverage; the largest payer was Abbvie Inc. The 50,334 providers of this specialty with any payment received $1,303.06 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.
Antonios Katsigiannis among 2,623 internal medicine physician records in Connecticut
Antonios Katsigiannis, M.D. 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 2006, is newer than 11% of them.
- NPI issued2006 · 11% of these records are older, 52% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileYes · 63% of these records are
- Graduated1993 · median 2004 among the 1,646 with a school on file
- Record last updated2019 · 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).
131 internal medicine physician records list a practice address in Stamford
They are 131 of the 2,774 NPPES records with a practice address in Stamford, and 2,623 internal medicine physician records in Connecticut.
All 2,623 in Connecticut → Every provider in Stamford → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- Uday Desai, M.D.Stamford, CT 069051124122148
- Vernetta Gallop, MDStamford, CT 069051811981202
- Erica Goldberger, M.D.Stamford, CT 069051053419648
- Terrance Hanlon, MDStamford, CT 069051922052695
- Tulin Koparan, MDStamford, CT 069051710045703
- Santi Neuberger, M.D.Stamford, CT 069051013024736
- David Radin, MDStamford, CT 069051225076193
- Remi Rosenberg, MDStamford, CT 069051932204203
Common questions
What is Antonios Katsigiannis, M.D.'s NPI number?
Antonios Katsigiannis, M.D.'s National Provider Identifier (NPI) is 1629157276, issued on Nov 3, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Antonios Katsigiannis, M.D. located?
The NPPES record lists a practice address at 90 Morgan St, Stamford, CT, 06905. Phone: (203) 323-8437. Providers update this record themselves, so call before visiting.
How can I verify Antonios Katsigiannis, M.D.'s license?
NPPES lists Connecticut license number 035140, 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 Antonios Katsigiannis, M.D. prescribe under Medicare Part D?
In 2024, Antonios Katsigiannis, M.D. had 3,509 Medicare Part D claims for 165 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.