HealthCareAtlasUSA

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Doctors / CT

WILLIAM J GIESEN, MD

INTERNAL MEDICINE

Medical school: GEORGETOWN UNIVERSITY SCHOOL OF MEDICINE

Graduated: 1975

NPI: 1124104724

Practice Locations (1)

1500 POST RD

DARIEN, CT 068205935

2036552516

Source: CMS National Downloadable File, September 2026.

WILLIAM GIESEN, MD | HealthCareAtlasUSA