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Internal Medicine

Tracy M. Riordan, MD

Works at hospitals in Crystal City, MO · Saint Louis, MO · Missouri

Summary

Tracy M. Riordan, MD (Internal Medicine) is listed by Medicare at 3 hospitals in Crystal City, MO and Saint Louis, MO. NPI 1124094362. 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 Tracy M. Riordan, 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

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
26Years since medical school (graduated 2000)
Saint Louis University School Of MedicineMedical school
FemaleGender (as listed)
Mercy Clinic East CommunitiesGroup practice

Quick answers

Which hospitals does Tracy M. Riordan work at?
Medicare's official clinician data lists Tracy M. Riordan at 3 hospitals: Mercy Hospital Jefferson, Mercy Hospital South and Mercy Hospital St Louis. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Tracy M. Riordan see patients?
Medicare's clinician data lists 1 practice location in Imperial, MO. Call before your visit to confirm the address.
What is Tracy M. Riordan's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Tracy M. Riordan accept Medicare assignment?
Yes. Medicare's clinician data says Tracy M. Riordan 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 Tracy M. Riordan?
(636) 741-3130, as listed in official Medicare / NPI Registry data.
What is Tracy M. Riordan's NPI number?
1124094362. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Tracy M. Riordan works

Medicare's Facility Affiliation Data lists Tracy M. Riordan 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 Tracy M. Riordan is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Tracy M. Riordan as a member of this group (CMS data updated 2026-10-02).

  • Mercy Clinic East Communities571 clinicians in the group

Specialties

Find other Internal Medicine doctors in Missouri →

Other internal medicine doctors in Missouri

Clinicians with the same Medicare primary specialty in Missouri — not a recommendation.

All internal medicine doctors in Missouri →

Clinician information

CredentialMD
Medical schoolSaint Louis University School Of Medicine
Graduation year2000
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1124094362
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