HealthCareAtlasUSA

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Doctors / IA

MARK C JOHNSON, MD

ENDOCRINOLOGY

Medical school: UNIVERSITY OF IOWA, RJ & L CARVER COLLEGE OF MEDICINE

Graduated: 1977

Also: INTERNAL MEDICINE

NPI: 1013923127

Practice Locations (1)

NORTH IOWA MERCY CLINICS

910 N EISENHOWER AVE, MERCYONE DIABETES CARE

MASON CITY, IA 504011525

6414287799

Source: CMS National Downloadable File, September 2026.

MARK JOHNSON, MD | HealthCareAtlasUSA