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Hospitalist

Theodore Hartenstein, MD

Works at hospitals in Middletown, CT · Connecticut

Summary

Theodore Hartenstein, MD (Hospitalist) is listed by Medicare at 1 hospital in Middletown, CT. NPI 1225256308. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Theodore Hartenstein, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

HospitalistPrimary specialty
YesAccepts Medicare assignment
20Years since medical school (graduated 2006)
University Of Massachusetts Medical SchoolMedical school
MaleGender (as listed)
Middlesex HospitalGroup practice

Quick answers

Which hospitals does Theodore Hartenstein work at?
Medicare's official clinician data lists Theodore Hartenstein at 1 hospital: Middlesex Hospital. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Theodore Hartenstein see patients?
Medicare's clinician data lists 1 practice location in Middletown, CT. Call before your visit to confirm the address.
What is Theodore Hartenstein's specialty?
Medicare lists Hospitalist as the primary specialty.
Does Theodore Hartenstein accept Medicare assignment?
Yes. Medicare's clinician data says Theodore Hartenstein accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Theodore Hartenstein?
(860) 358-5322, as listed in official Medicare / NPI Registry data.
What is Theodore Hartenstein's NPI number?
1225256308. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Theodore Hartenstein works

Medicare's Facility Affiliation Data lists Theodore Hartenstein at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Theodore Hartenstein is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Theodore Hartenstein as a member of this group (CMS data updated 2026-10-02).

  • Middlesex Hospital234 clinicians in the group

Specialties

Find other Hospitalist doctors in Connecticut →

Other hospitalists in Middletown

Clinicians with the same Medicare primary specialty in Middletown, CT — not a recommendation.

All hospitalists in Middletown →

Clinician information

CredentialMD
Medical schoolUniversity Of Massachusetts Medical School
Graduation year2006
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1225256308
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians