Catherine Louise Ash, M.D.
Internal Medicine Physician · Edwardsville, IL
Catherine Louise Ash, M.D. is an internal medicine physician with a practice address in Edwardsville, Illinois, and NPI 1861874059, issued on Jun 24, 2015. Check the license (Illinois 036177442, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Catherine Louise Ash
- Credential
- M.D.
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License numbers
- 036177442 IL
2018022561 MO
Self-reported in NPPES; status is on the state search - Practice location
- 2122 Troy RD Ste 130, Edwardsville, IL 62025
- Phone
- (618) 800-4500
- Enumerated
- Jun 24, 2015
- Record last updated
- Dec 18, 2025
- Fax
- (618) 800-4501
- Medicare enrollment
- Enrolled (PECOS I20260415001953); accepts Medicare assignment
- Medical or professional school
- Saint Louis University School Of Medicine, 2015
- Telehealth
- Offers telehealth (CMS)
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 7,238 in Illinois → Look up another NPI →
Also registered at 2122 Troy RD Ste 130
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Sisay Michael Abraham, MDFamily Medicine Physician1184088312
- Megan Cox, DNP, FNPFamily Nurse Practitioner1326504135
- Marion Dessalines, PA-CPhysician Assistant1548082647
- Mei Huang, M.D.Gastroenterology Physician1417972597
- Ranita Keller, FNPFamily Nurse Practitioner1083096895
- Adrienne Kinney, NPNurse Practitioner1710489349
Verify Catherine Louise Ash in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIllinois Department of Financial and Professional Regulation
Search for license 036177442Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
72% more Medicare Part D claims than the average internal medicine physician in 2024
5,457 Medicare Part D claims for 571 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 12% of claims. 308 claims were for opioids.
Most prescribed
- Atorvastatin Calcium331 claims
- Amlodipine Besylate210 claims
- Levothyroxine Sodium202 claims
- Lisinopril172 claims
- Losartan Potassium139 claims
- Trazodone Hcl136 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Industry payments in 2024: $87.56
3 payments; by number, the most common kind was food and beverage; the largest payer was Lilly USA, LLC. The 50,334 providers of this specialty with any payment received $1,303.06 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Bills Medicare through 3 group practices
- Aging Well Health Care, LLCSaint Louis, MO
- Fairview Heights Medical Group SCEdwardsville, IL
- Mercy Clinic East CommunitiesSaint Louis, MO
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Catherine Louise Ash among 7,238 internal medicine physician records in Illinois
Catherine Louise Ash, M.D. is one of 7,238 internal medicine physician records with a practice address in Illinois. 73% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2015, is newer than 61% of them.
- NPI issued2015 · 61% of these records are older, 37% newer
- In a Medicare fileYes · 73% of these records are
- In the CMS Doctors and Clinicians fileYes · 50% of these records are
- Graduated2015 · median 2003 among the 3,580 with a school on file
- Record last updated2025 · 47% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Internal Medicine Physician providers in Illinois
There are 7,238 internal medicine physician records in Illinois.
All 7,238 in Illinois → Every provider in Edwardsville → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- William Bonzelet, MDEdwardsville, IL 620251548224686
- Nueki Naate, MDEdwardsville, IL 620251528588928
- Kelly Rourke, M.D.Edwardsville, IL 620251033185285
- David Yablonsky, D.O.Edwardsville, IL 620251780665901
- Renan Mapue, MDCarrollton, IL 620161205002052
- Michael McNear, MDCarrollton, IL 620161619934304
- Abiodun Sangoseni, MDGlen Carbon, IL 620341194710483
- Michael Adams, MDGranite City, IL 620401851383301
Common questions
What is Catherine Louise Ash, M.D.'s NPI number?
Catherine Louise Ash, M.D.'s National Provider Identifier (NPI) is 1861874059, issued on Jun 24, 2015. An NPI identifies a provider in billing; it is not a license.
Where is Catherine Louise Ash, M.D. located?
The NPPES record lists a practice address at 2122 Troy RD Ste 130, Edwardsville, IL, 62025. Phone: (618) 800-4500. Providers update this record themselves, so call before visiting.
How can I verify Catherine Louise Ash, M.D.'s license?
NPPES lists Illinois license number 036177442, as entered by the provider. Search the Illinois Department of Financial and Professional Regulation at https://idfpr.illinois.gov/checklicense.html. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Catherine Louise Ash, M.D. prescribe under Medicare Part D?
In 2024, Catherine Louise Ash, M.D. had 5,457 Medicare Part D claims for 571 beneficiaries; the average among internal medicine physician prescribers was 3,176. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.