HealthCareAtlasUSA

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Doctors / IA

WILLIAM J RIESEN, MD

INTERNAL MEDICINE

Medical school: PERELMAN SCHOOL OF MED AT THE UNIVERSITY OF PENNSYLVANIA

Graduated: 1993

NPI: 1548377997

Practice Locations (2)

NORTH IOWA MERCY CLINICS

1000 4TH ST SW

MASON CITY, IA 504012800

NORTH IOWA MERCY CLINICS

1010 4TH ST SW

MASON CITY, IA 504012857

Source: CMS National Downloadable File, September 2026.

WILLIAM RIESEN, MD | HealthCareAtlasUSA