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

Dr. Larry Johnston, DO

Individual provider Gastroenterology Physician · NPI 1386036333

Dr. Larry Johnston, DO is a Gastroenterology in Ames, Iowa. Graduated from Oklahoma State University College of Osteopathic Medicine in 2015, 11 years ago. Practices with McFarland Clinic PC, a 353-clinician group and accepts Medicare assignment. Licensed in Iowa and Oklahoma.

Years since qualifying
11
Trained at
Oklahoma State University College of Osteopathic Medicine
Licensed in
IA, OK
In the registry since
2015
Specialties on file
2
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 →

Practice location Address checks out

1215 Duff Ave
Ames, IA 50010-5469
Phone: (515) 239-4450
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Gastroenterology Physician (primary) Taxonomy 207RG0100X · Licence 05983 (IA)
Internal Medicine Physician Taxonomy 207R00000X · Licence 6004 (OK)

Record details

NPI number1386036333
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorYes
NPI enumeratedFebruary 28, 2015
Last updated in NPPESAugust 2, 2022
Certification dateAugust 2, 2022
Mailing address1215 Duff Ave, Ames, IA 50010-5469

Medicare enrollment

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

Medicare specialtyGASTROENTEROLOGY
Medical schoolOKLAHOMA STATE UNIVERSITY COLLEGE OF OSTEOPATHIC MEDICINE
Graduated 2015 (11 years in practice)
Group practice McFarland Clinic Pc — 353 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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