Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

Thomas Paul Marnejon, DO

Individual provider Internal Medicine Physician · NPI 1891898607

Thomas Paul Marnejon, DO practises Internal Medicine in Youngstown, Ohio. Graduated from Philadelphia College of Osteopathic Medicine in 1987, 39 years ago. Practices with Mercy Health Physicians Youngstown, LLC, a 117-clinician group and accepts Medicare assignment. Licensed in Ohio.

Years since qualifying
39
Trained at
Philadelphia College of Osteopathic Medicine
Licensed in
OH
In the registry since
2006
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

1001 Covington St
Youngstown, OH 44510-1617
Phone: (330) 480-2616
Fax: (330) 480-7979
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 34004912 (OH)

Record details

NPI number1891898607
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorNo
NPI enumeratedSeptember 7, 2006
Last updated in NPPESApril 13, 2019

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyINTERNAL MEDICINE
Medical schoolPHILADELPHIA COLLEGE OF OSTEOPATHIC MEDICINE
Graduated 1987 (39 years in practice)
Group practice Mercy Health Physicians Youngstown, Llc — 117 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations3 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients56
Services billed 71 a service is one billed item, such as a visit, a test or a procedure
Average patient age66

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

  • Mh St Elizabeth Youngstown Hospital Hospital · Youngstown, OH

Colleagues at Mercy Health Physicians Youngstown, LLC

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 117 clinicians in the practice; 12 are shown here.

Other providers in Youngstown