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Physician Assistant

Haydan E. Ommen

Works at hospitals in Saint Louis, MO · Missouri

Summary

Haydan E. Ommen (Physician Assistant) is listed by Medicare at 1 hospital in Saint Louis, MO. NPI 1699525121. 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 Haydan E. Ommen, 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

Physician AssistantPrimary specialty
YesAccepts Medicare assignment
3Years since medical school (graduated 2023)
FemaleGender (as listed)
Mercy Clinic Surgical Specialists LLCGroup practice (+1 more)

Quick answers

Which hospitals does Haydan E. Ommen work at?
Medicare's official clinician data lists Haydan E. Ommen at 1 hospital: Mercy Hospital South. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Haydan E. Ommen see patients?
Medicare's clinician data lists 4 practice locations, including Saint Louis, MO and Chesterfield, MO. Call before your visit to confirm the address.
What is Haydan E. Ommen's specialty?
Medicare lists Physician Assistant as the primary specialty.
Does Haydan E. Ommen accept Medicare assignment?
Yes. Medicare's clinician data says Haydan E. Ommen 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 Haydan E. Ommen?
(314) 525-4440, as listed in official Medicare / NPI Registry data.
What is Haydan E. Ommen's NPI number?
1699525121. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Haydan E. Ommen works

Medicare's Facility Affiliation Data lists Haydan E. Ommen 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 Haydan E. Ommen is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Haydan E. Ommen as a member of these groups (CMS data updated 2026-10-02).

  • Mercy Clinic Surgical Specialists LLC182 clinicians in the group
  • Orthopedic Center of St Louis Img LLC6 clinicians in the group

Specialties

Find other clinicians: Physician Assistant, Missouri →

Other physician assistants in Saint Louis

Clinicians with the same Medicare primary specialty in Saint Louis, MO — not a recommendation.

All physician assistants in Saint Louis →

Clinician information

Graduation year2023
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1699525121
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