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Doctors / MA

WILLIAM CHARLES O CALLAHAN, MD

EMERGENCY MEDICINE

Medical school: UNIVERSITY OF MASSACHUSETTS MEDICAL SCHOOL

Graduated: 1990

NPI: 1114964186

Practice Locations (1)

URGENT CARE SPECIALISTS PC

5 SHREWSBURY ST, SUITE D

HOLDEN, MA 015201960

5088293800

Source: CMS National Downloadable File, September 2026.

WILLIAM O CALLAHAN, MD | HealthCareAtlasUSA