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

Douglas T Summerfield, MD

Individual provider Internal Medicine Physician · NPI 1518120633

Douglas T Summerfield, MD is an Internal Medicine in Mason City, Iowa. Graduated from Creighton University School of Medicine in 2007, 19 years ago. Practices with North Iowa Mercy Clinics, a 300-clinician group and accepts Medicare assignment. Licensed in Iowa, Minnesota and Virginia.

Years since qualifying
19
Trained at
Creighton University School of Medicine
Licensed in
IA, MN, VA
In the registry since
2008
Specialties on file
4
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

1000 4th St SW
Mason City, IA 50401-2800
Phone: (641) 428-6999
Fax: (641) 428-6678
Show map & directions

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

Specialties & licences

Critical Care Medicine (Internal Medicine) Physician (primary) Taxonomy 207RC0200X · Licence 41014 (IA)
Internal Medicine Physician Taxonomy 207R00000X · Licence 0101246408 (VA)
Critical Care Medicine (Internal Medicine) Physician Taxonomy 207RC0200X · Licence 54611 (MN)
Critical Care Medicine (Internal Medicine) Physician Taxonomy 207RC0200X · Licence 105450 (MN)

Record details

NPI number1518120633
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJuly 9, 2008
Last updated in NPPESMay 30, 2023
Certification dateMay 30, 2023
Mailing address621 S Illinois Ave Ste 103, Mason City, IA 50401-5489

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolCREIGHTON UNIVERSITY SCHOOL OF MEDICINE
Graduated 2007 (19 years in practice)
Group practice North Iowa Mercy Clinics — 300 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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