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ALISON DEREMIGIS THOMASSON M.D.
NPI 1245644822
Pediatrics - Pediatric Critical Care Medicine in Saint Louis, MO

Active since June 11, 2014PECOS Enrolled
621 S NEW BALLAS RD STE 6009B, SAINT LOUIS, MO 63141(314) 251-6598(314) 251-7990 Get Directions Write a Review

NPPES record last updated: May 2, 2023. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: May 2, 2023, Jun 16, 2020 (2 updates tracked since 2020).

About Alison Deremigis Thomasson M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

ALISON DEREMIGIS THOMASSON M.D. (NPI 1245644822) is an individual pediatric critical care medicine provider in Saint Louis, Missouri, licensed in Missouri (2020020171) and active in the NPI registry since June 2014. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1245644822
Entity TypeIndividualFemale
Primary Taxonomy2080P0203X
Provider Legal NameALISON DEREMIGIS THOMASSONCredential: M.D.
Location Address621 S NEW BALLAS RD STE 6009BSaint Louis, MO 63141-8273
Mailing Address621 S New Ballas Rd Ste 6009bSaint Louis, MO 63141-8273 · (314) 251-6598 · Fax (314) 251-7990
Phone(314) 251-6598
Fax(314) 251-7990
Sole ProprietorNo
Enumeration DateJune 11, 2014
Last NPPES UpdateMay 2, 20232 updates tracked since enumeration
NPPES CertifiedMay 2, 2023
✔ NPI 1245644822 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPediatrics · Pediatric Critical Care MedicineAllopathic & Osteopathic Physicians
Taxonomy Code2080P0203X
License✔ Licensed in MO · 2020020171
Definition
A pediatrician expert in advanced life support for children from the term or near-term neonate to the adolescent. This competence extends to the critical care management of life-threatening organ system failure from any cause in both medical and surgical patients and to the support of vital physiological functions. This specialist may have administrative responsibilities for intensive care units and also facilitates patient care among other specialists.
621 S NEW BALLAS RD STE 6009B, Saint Louis, MO 63141
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Anthem Blue Cross and Blue Shield.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Alison Deremigis Thomasson M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Alison Thomasson reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Mercy Hospitals East Communities
Same address
Audiologist
621 S NEW BALLAS RD STE 385A
Saint Louis, MO 63141
  • Reassigned Medicare billing, Missouri enrollment
  • 241 clinicians in this Medicare group
NPI 1255790762 (314) 251-5850

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Alison Thomasson's NPI number?

The NPI number for Alison Thomasson is 1245644822. It was assigned to this individual provider in the NPPES registry on June 11, 2014.

Where is Alison Thomasson located?

Alison Thomasson practices at 621 S New Ballas Rd Ste 6009B, Saint Louis, MO 63141. The listed phone number is (314) 251-6598.

What is Alison Thomasson's specialty?

The primary specialty registered for this NPI is Pediatrics, specializing in Pediatric Critical Care Medicine, with taxonomy code 2080P0203X.

Is Alison Thomasson enrolled in Medicare?

Yes. Alison Thomasson is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Alison Thomasson's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Alison Thomasson reassigns Medicare benefits to Mercy Hospitals East Communities (Saint Louis, MO). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Alison Thomasson's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Alison Thomasson accept?

Health plans from Anthem Blue Cross and Blue Shield list Alison Thomasson as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

When was this NPI record last updated?

The NPPES record for Alison Thomasson was last updated on May 2, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.