Dr. Thomas H Welsh , MD
Internal Medicine • Mesa, AZ
2550 N Thunderbird Circle, Suite 303
Mesa, AZ 85215
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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Dr. Thomas Welsh is listed in NPPES under Internal Medicine.
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NPI assigned on May 10, 2006; this date does not establish years in practice.
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Published CMS data list 67 Medicare Part D prescriptions, including refills, in 2024.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. Published rows only; this is not a quality measure.
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Published Part D records, 2024:
- Prednisone — 30 prescription fills, including refills.
- Azithromycin — 20 prescription fills, including refills.
- Amoxicillin-Clavulanate Potass (Amoxicillin/Potassium Clav) — 17 prescription fills, including refills.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. 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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Fewer Part D prescriptions than 80% of clinicians listed under Internal Medicine in Mesa, AZ (2024, 97 clinicians with data). Median for this group: 681. Middle half: 146 to 4,961.
Fewer Part D prescriptions than 80% of clinicians listed under Internal Medicine in Arizona (2024, 1,547 clinicians with data). Median for this group: 848. Middle half: 130 to 4,070.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2024. Billing and prescribing volume is not a quality rating.
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Medicare Part D prescriptions went from 40 in 2020 to 67 in 2024.
Source: CMS, Medicare Part D Prescribers – by Provider and Drug, 2020–2024.
Practice Location & Contact Primary Location
2550 N Thunderbird Circle
Suite 303
Mesa, AZ 85215
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
Internal Medicine: NPPES taxonomy is a reported classification, not proof of board certification.
30-day fills
67 standardized 30-day fills in 2024
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
$271 in 2024
The total cost of these prescriptions in 2024, 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, 2024.
Industry payments (Open Payments)
No Open Payments records are listed for this clinician for 2019–2025.
NPI first issued
2006
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, CMS release of October 2, 2026; 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, CMS release of October 2, 2026.
Enrolled in Medicare (PECOS)
Dr. Welsh has a Medicare enrollment record in PECOS, the CMS system clinicians use to enroll so they can bill Medicare or order services for people with Medicare.
It does not show whether the clinician accepts assignment, is in your plan's network, or is taking new patients.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Can order Medicare-covered services
CMS lists Dr. Welsh as eligible to order or refer Medicare Part B clinical laboratory and imaging services, durable medical equipment (DME) and home health services for people with Medicare.
Medicare pays for these items and services only when they are ordered by an eligible clinician.
What this does not show: Can order Medicare-covered services
It does not mean the clinician offers these services directly.
Source: CMS Medicare Fee-For-Service Public Provider Enrollment (PECOS); CMS Order and Referring file.
Compared with the same specialty in Mesa and Arizona
Billing and prescribing volume is not a quality rating.
Medicare Part D prescriptions
Fewer Part D prescriptions than 80% of clinicians listed under Internal Medicine in Mesa, AZ (2024, 97 clinicians with data). Median for this group: 681. Middle half: 146 to 4,961.
Fewer Part D prescriptions than 80% of clinicians listed under Internal Medicine in Arizona (2024, 1,547 clinicians with data). Median for this group: 848. Middle half: 130 to 4,070.
Part D drug cost
A lower Part D drug cost than 90% of clinicians listed under Internal Medicine in Mesa, AZ (2024, 97 clinicians with data). Median for this group: $33,316. Middle half: $5,134 to $417,039.
A lower Part D drug cost than 90% of clinicians listed under Internal Medicine in Arizona (2024, 1,547 clinicians with data). Median for this group: $58,124. Middle half: $6,357 to $317,963.
165 active clinicians are listed under Internal Medicine with a practice address in Mesa, AZ (2,908 in Arizona).
Addresses are self-reported to NPPES and may be out of date.
Telehealth indicator in Mesa
15.2% of these 165 clinicians have the CMS telehealth indicator.
61.8% of these 165 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 D prescriptions
Medicare Part D prescriptions increased 68% from 40 in 2020 to 67 in 2024.
- 2020: 40
- 2021: 48
- 2022: 146
- 2023: 79
- 2024: 67
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30-day fills
30-day fills increased 68% from 40 in 2020 to 67 in 2024.
- 2020: 40
- 2021: 48
- 2022: 146
- 2023: 79
- 2024: 67
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Part D drug cost
Part D drug cost went from $180 in 2020 to $271 in 2024.
- 2020: $180
- 2021: $357
- 2022: $1,261
- 2023: $662
- 2024: $271
Sources: CMS Medicare Part D Prescribers (2024), CMS Doctors and Clinicians, CMS release of October 2, 2026, CMS NPPES NPI Registry. Specialty names follow the NUCC Health Care Provider Taxonomy.
Text: T-MedInfo · Report an error.
Medicare Part D Prescribing Profile & Medications
Medicare Part D prescriptions filled, including refills, in 2024.
| Brand Name | Generic Name | Prescriptions | Day Supply | Total Cost | Patients |
|---|---|---|---|---|---|
| Prednisone | Prednisone | 30 | 199 | $72.67 | 28 |
| Azithromycin | Azithromycin | 20 | 100 | $65.36 | 20 |
| Amoxicillin-Clavulanate Potass | Amoxicillin/Potassium Clav | 17 | 109 | $133.29 | 17 |
Source: CMS Part D by Provider and Drug, 2024; rows below 11 claims omitted by CMS; volume isn’t quality. Privacy limits
Specialties & License Numbers Reported to NPPES
NUCC Taxonomy Code: 207R00000X
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
Medicare (PECOS) Enrollment & Ordering Eligibility
Source: CMS PECOSPRACTITIONER - INTERNAL MEDICINE
I20111026000130
AZ
2163405192
Sources: CMS Provider Enrollment and Order and Referring. Medicare enrollment is a billing status, not an accreditation or quality rating.
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
Doctor of Medicine (M.D.)
Emergency Medicine
Physician Assistant
Physician Assistant
Physician Assistant (Certified)
Physician Assistant
Physician Assistant - Medical
Physician Assistant (Certified)
Nurse Practitioner - Family
Family Nurse Practitioner (Certified)
Career & Practice History
NPI enumerated May 10, 2006.
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 November 2026.
NPI Administrative Meta
Other Internal Medicine Providers in Mesa
- Dr. Mustafa Malik, MD
- Dr. Travis Fisher, MD
- Dr. Gabriel Valle-Eger, MD
- Dr. Dheeraj Bobba, MD
- Dr. Usma Ahmad, MD MBBS
- Dr. Yunuen Valenzuela, MD
Mailing Address
1202 N Fiji Way
Gilbert, AZ 852342887
Phone: 4355904199