HealthCareAtlasUSA

This site republishes official CMS/Medicare Care Compare data. It is not medical advice and does not recommend any specific hospital or treatment — for medical decisions, talk to a doctor.

Doctors / CA

MARK C OBRIEN, DO

INTERNAL MEDICINE

Medical school: MICHIGAN STATE UNIVERSITY COLLEGE OF OSTEOPATHIC MEDICINE

Graduated: 1987

Offers telehealth

NPI: 1497744247

Practice Locations (1)

161 THUNDER DR, SUITE 210

VISTA, CA 920836052

7602166500

Source: CMS National Downloadable File, September 2026.

MARK OBRIEN, DO | HealthCareAtlasUSA