Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Mariel Fahnline McGuiness, MD

Individual provider Internal Medicine Physician · NPI 1356978399

Mariel Fahnline McGuiness, MD is an Internal Medicine in Hilliard, Ohio. Graduated from Ohio State University College of Medicine in 2020, 6 years ago. Practices with Osu General Internal Medicine LLC, a 266-clinician group, works from 12 locations and accepts Medicare assignment. Licensed in Ohio.

Years since qualifying
6
Trained at
Ohio State University College of Medicine
Licensed in
OH
In the registry since
2020
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

3691 Ridge Mill Dr
Hilliard, OH 43026-7752
Phone: (614) 293-5123
Fax: (614) 293-4890
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

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

Additional practice locations (11)

  • 26 Hospital Dr, Athens, OH 45701-2471 — (614) 722-6200
  • 700 Childrens Dr, Columbus, OH 43205-2664 — (614) 722-6200
  • 555 S 18th St, Columbus, OH 43205-2654 — (614) 722-6200
  • 1800 Heinzerling Dr, Columbus, OH 43223-3642 — (614) 722-6200
  • 1405 S High St, Columbus, OH 43207-1043 — (614) 355-9000
  • 7450 Hospital Dr, Dublin, OH 43016-9642 — (614) 722-6200
  • 5665 Venture Dr, Dublin, OH 43017-2159 — (614) 722-6200
  • 4363 All Seasons Dr, Hilliard, OH 43026-2050 — (614) 722-6200
  • 830 W High St, Lima, OH 45801-3971 — (614) 726-6200
  • 150 W Main St, New Albany, OH 43054-9229 — (614) 722-6200
  • 433 N Cleveland Ave, Westerville, OH 43082-8095 — (614) 722-6200

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 35.150329 (OH)
Pediatrics Physician Taxonomy 208000000X · Licence 35.150329 (OH)

Record details

NPI number1356978399
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedMarch 26, 2020
Last updated in NPPESFebruary 26, 2026
Certification dateFebruary 26, 2026

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Also practisesPEDIATRIC MEDICINE
Medical schoolOHIO STATE UNIVERSITY COLLEGE OF MEDICINE
Graduated 2020 (6 years in practice)
Group practice Osu General Internal Medicine Llc — 266 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Other providers in Hilliard