Ayn Larson , PA
Physician Assistant • Mesa, AZ
1810 S Crismon Rd Ste 191
Mesa, AZ 852093900
This profile restates public CMS/NPPES data; T-MedInfo gives no medical advice — consult a licensed professional, and call 911 for emergencies.
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NPI assigned on August 20, 2015; this date does not establish years in practice.
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Published CMS data list 41 Original Medicare Part B services in 2019.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2019. Published rows only; this is not a quality measure.
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Published Part B service records, 2019:
- 99213 — Established patient outpatient office visit: 29 service units.
- 99203 — New patient outpatient office visit: 12 service units.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2019. Units differ by code; these are not visits or a measure of quality.
CPT® only copyright 2018 American Medical Association. All rights reserved. Service names are shortened from CPT Consumer Friendly Descriptors (CMS data, 2019). CPT notice
See the full table · Guide: How to read Medicare Part B data
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Published CMS data list 11 Medicare Part D prescriptions, including refills, in 2022.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2022. Published rows only; this is not a quality measure.
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Published Part D records, 2022:
- Linzess (Linaclotide) — 11 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2022. Drug names come from pharmacy claims. Listing a drug here is not an endorsement or a recommendation.
See the full table · Guide: How to read Medicare Part D prescriber data
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Medicare Part D prescriptions went from 89 in 2016 to 11 in 2022.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2016–2022.
Practice Location & Contact Primary Location
1810 S Crismon Rd Ste 191
Mesa, AZ 852093900
Matched by practice address or phone in NPPES. A shared address or phone does not confirm that this clinician works there.
What Public CMS Data Show
Physician Assistant: NPPES taxonomy is a reported classification, not proof of board certification.
Medicare-allowed amount
About $2,870 in 2019
The total amount Medicare approved for these services in 2019. It includes what Medicare paid and what patients or their other insurance owed, such as the deductible and coinsurance.
It shows the total cost of this clinician's Original Medicare services under Medicare's fee rules.
What this does not show: Medicare-allowed amount
This is not the clinician's income. Part of it can go to a clinic or group practice, staff, equipment or drugs. It is not the price you will pay.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2019.
Paid by Medicare
About $2,237 in 2019
The part of the Medicare-allowed amount that Medicare itself paid in 2019, after patients' deductibles and coinsurance.
The gap between the allowed amount and this number is roughly what patients and their other insurance paid.
What this does not show: Paid by Medicare
This is not the clinician's income and not a measure of quality.
Source: CMS, Medicare Physician & Other Practitioners – by Provider and Service, 2019.
30-day fills
17 standardized 30-day fills in 2022
CMS converts prescriptions to 30-day supplies so they can be compared. A 90-day prescription counts as about three 30-day fills.
What this does not show: 30-day fills
It is not a count of patients and not a measure of quality.
Part D drug cost
$8,803 in 2022
The total cost of these prescriptions in 2022, paid by Medicare drug plans, patients and other payers together.
It shows the total spending on drugs this clinician prescribed, not what any one patient paid.
What this does not show: Part D drug cost
A higher cost often reflects the type of medicines a specialty uses. It is not your out-of-pocket cost and not a measure of quality.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2022.
Industry payments (Open Payments)
Fewer than 11 payment records totaling $19.18 in 2024
Drug and medical device companies must report certain payments to doctors and some other clinicians to CMS, such as meals, travel, speaking fees or research funding.
It shows reported financial ties between this clinician and companies. You can ask your clinician about them.
These records are submitted by drug and medical device companies, and a reported payment does not necessarily mean the financial relationship is improper.
General: payments not tied to research, such as meals, travel, consulting or speaking fees.
A reported payment does not necessarily mean the financial relationship is improper. Research payments can go to a hospital or university for a study the clinician leads, not to the clinician personally. Clinicians can dispute records with the company that reported them.
Source: CMS Open Payments, program year 2024.
NPI first issued
2015
The year this clinician's National Provider Identifier (NPI) was issued. An NPI is a unique 10-digit ID that US health care providers use for billing.
What this does not show: NPI first issued
NPIs have been issued only since 2005, so this year is not necessarily when the clinician started practicing.
Source: CMS NPPES NPI Registry.
Medicare assignment not listed
CMS data do not show whether this clinician accepts Medicare assignment. This does not mean they do not accept Medicare. Ask the office.
Medicare assignment applies to Original Medicare. It does not tell you whether the clinician is in a Medicare Advantage plan's network, accepts other insurance, or is taking new patients.
Source: CMS Doctors and Clinicians; Medicare.gov, “Does your provider accept Medicare as full payment?”
No telehealth indicator
CMS shows this indicator only when recent Medicare claims include telehealth services. The clinician may still offer telehealth; ask the office.
Source: CMS, Telehealth Indicator on Medicare Care Compare (fact sheet, January 2023); CMS Doctors and Clinicians.
Compared with the same specialty in Mesa and Arizona
Billing and prescribing volume is not a quality rating.
Medicare Part B
Comparisons use 2024 data. The latest CMS data for Ayn Larson are from 2019.
Medicare Part D
Comparisons use 2024 data. The latest CMS data for Ayn Larson are from 2022.
472 active clinicians are listed under Physician Assistant with a practice address in Mesa, AZ (3,673 in Arizona).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Mesa
8.3% of these 472 clinicians have the CMS telehealth indicator.
37.1% of these 472 clinicians are listed by CMS as accepting Medicare assignment.
CMS data by year
Changes may reflect reporting, coverage or privacy limits, not changes in care quality.
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Medicare Part B services
CMS data for Medicare Part B services are available for 2019 only.
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Medicare-allowed amount
CMS data for Medicare-allowed amount are available for 2019 only.
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Paid by Medicare
CMS data for Medicare payment amount are available for 2019 only.
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Medicare Part D prescriptions
Medicare Part D prescriptions decreased 88% from 89 in 2016 to 11 in 2022.
- 2016: 89
- 2017: 587
- 2018: 375
- 2019: 260
- 2022: 11
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30-day fills
30-day fills decreased 85% from 111 in 2016 to 17 in 2022.
- 2016: 111
- 2017: 736
- 2018: 569
- 2019: 335
- 2022: 17
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Part D drug cost
Part D drug cost decreased 98% from $447,548 in 2016 to $8,803 in 2022.
- 2016: $447,548
- 2017: $108,814
- 2018: $75,051
- 2019: $63,450
- 2022: $8,803
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Industry payments (Open Payments)
Industry payments (Open Payments) went from $317.27 in 2021 to $19.18 in 2024.
- 2021: $317.27
- 2022: $370.93
- 2023: $50.54
- 2024: $19.18
Sources: CMS Medicare Physician & Other Practitioners (2019), CMS Medicare Part D Prescribers (2022), CMS Open Payments (2024), CMS Doctors and Clinicians, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo · Report an error.
Pharma & Medical Device Financial Disclosures
Payments and other transfers of value that drug and medical device companies reported to CMS Open Payments
Program year 2024 (payments made January 1 – December 31, 2024): fewer than 11 records totaling $19.18.
| Manufacturer | Payment Nature | Product | Type | Amount ($) |
|---|---|---|---|---|
| ABBVIE INC. |
Food and Beverage
In-kind items and services
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MAVYRET | General | $19.18 |
Source: CMS Open Payments, program year 2024, released June 30, 2026.
Performed Procedures & Service Volume
CPT® is a registered trademark of the American Medical Association. CPT codes, descriptions and other data only are copyright 2018 American Medical Association. All rights reserved. Applicable FARS/HHSARS apply. Descriptions of CPT codes are the AMA's CPT Consumer Friendly Descriptors as published by CMS in the Medicare Physician & Other Practitioners – by Provider and Service data, 2019; they are plain-language summaries, not for clinical coding or documentation. HCPCS Level II codes and descriptions are from CMS. Fee schedules, relative value units, conversion factors and/or related components are not assigned by the AMA, are not part of CPT, and the AMA is not recommending their use. The AMA does not directly or indirectly practice medicine or dispense medical services. The AMA assumes no liability for data contained or not contained herein.
| HCPCS Code | Services | Patients | Submitted Charge | Medicare Allowed |
|---|---|---|---|---|
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99213
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more
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29 | 29 | $100.00 | $61.77 |
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99203
New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more
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12 | 12 | $165.00 | $89.93 |
Source: CMS Part B by Provider and Service, 2019; services under 11 beneficiaries omitted by CMS. Privacy limits
Submitted charges are billed amounts, not a price quote for your visit.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2022.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Linzess | Linaclotide | 11 | 510 | $8,802.75 | — |
Source: CMS Part D by Provider and Drug, 2022; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
NUCC Taxonomy Code: 363A00000X
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
NUCC Taxonomy Code: 363A00000X
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
Additional State Medicaid & Healthcare Payer Identifiers
Clinicians Sharing This Practice Address or Phone
Clinicians sharing this NPPES address, phone or fax; a shared contact does not mean they work together.
Internal Medicine - Gastroenterology
Doctor of Medicine (M.D.)
Nurse Practitioner - Family
Nurse Practitioner
Nurse Practitioner
Nurse Practitioner
Internal Medicine - Gastroenterology
Doctor of Medicine (M.D.)
Surgery
Doctor of Medicine (M.D.)
Surgery
Doctor of Medicine (M.D.)
Career & Practice History
NPI enumerated August 20, 2015.
No changes to the name, practice address, taxonomy or NPI status in this record have been observed in the monthly NPPES data files from January 2017 to August 2026.
NPI Administrative Meta
Other Physician Assistants in Mesa
- Carly Thomas, MPAS, PA-C
- Taylor Kovach, PA
- Cecilia Morales, PA-C
- Alicia Aldana, PA-C
- Patricia Layton, PA
- Stephanie Yu, PA-C
Mailing Address
1810 S Crismon Rd Ste 191
Mesa, AZ 852093900
Phone: 4803930575