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Physician Assistant

Alyssa Rose M. Duenas

Works at hospitals in O Fallon, IL · Illinois

Summary

Alyssa Rose M. Duenas is a physician assistant at 1512 N Green Mount Rd, O Fallon, IL 62269. Phone: (618) 624-3750. Accepts Medicare assignment. In 2024, Alyssa Rose M. Duenas had 277 Original Medicare patients and 311 services. NPI 1902216914. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

  • Specialty: Physician assistant
  • Address: 1512 N Green Mount Rd, O Fallon, IL 62269 · Directions (1 more location)
  • Phone: (618) 624‑3750
  • Medicare: Accepts Medicare assignment
  • Hospital: HSHS St Elizabeth's Hospital
  • Group practice: Vituity - Illinois Auc LLP
  • School: Oregon Health Sciences University School Of Medicine · graduated 2015
  • Gender (as listed): Female

From official Medicare data

This page shows what Medicare's official clinician data says about Alyssa Rose M. Duenas, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Alyssa Rose M. Duenas accept Medicare assignment?
Yes. Medicare's clinician data says Alyssa Rose M. Duenas accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
How many Medicare patients does Alyssa Rose M. Duenas see?
In 2024, CMS data shows 277 Original Medicare patients and 311 services for Alyssa Rose M. Duenas. This counts Original Medicare only and measures volume, not quality.
What is Alyssa Rose M. Duenas's NPI number?
1902216914. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Alyssa Rose M. Duenas, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients277
Services billed to Medicare311
Different services or procedures25
Participating Medicare providerYes
Average age of these patients72

Most frequent services

  1. Emergency department visit with high level of medical decision making (99285)153 services
  2. Emergency department visit with moderate level of medical decision making (99284)58 services
  3. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)31 services
  4. New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more (99204)22 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure75%
  • High cholesterol75%
  • Arthritis60%
  • Ischemic heart disease40%
  • Chronic kidney disease38%
  • Anxiety37%

Hospitals where Alyssa Rose M. Duenas works

Medicare's Facility Affiliation Data lists Alyssa Rose M. Duenas at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

  • HSHS St Elizabeth's HospitalO Fallon, IL · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 140187

Practice locations

Addresses where Alyssa Rose M. Duenas is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Alyssa Rose M. Duenas as a member of this group (CMS data updated October 2, 2026).

  • Vituity - Illinois Auc LLP36 clinicians in the group

Specialties

Find other clinicians: Physician Assistant, Illinois →

Other physician assistants in O Fallon

Clinicians with the same Medicare primary specialty in O Fallon, IL — not a recommendation.

All physician assistants in O Fallon →

Other clinicians in Vituity - Illinois Auc LLP

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

SchoolOregon Health Sciences University School Of Medicine
Graduation year2015
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1902216914
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 October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians