About
Dr. John A. Fagan earned his BA in Chemistry from the University of San Diego in 1982 before completing his medical degree at Loyola Stritch School of Medicine in Maywood, Illinois in 1986. He completed both his internship and family medicine residency at San Bernardino County Medical Center, finishing his training in 1989. He holds board certification as a Diplomate of the American Board of Family Medicine and carries a Certificate of Added Qualification in Geriatrics. That dual certification lets him serve patients across all ages, with particular depth in elder care.
Dr. Fagan has practiced for 35 years and serves as Medical Director of Aspen Family Medicine and Geriatrics since 2013. He maintains hospital affiliations with San Antonio Regional Hospital and Casa Colina Hospital and Centers for Healthcare. Professional organizations recognize his work: he has earned Top Doctor honors in 2009, 2012, 2015, 2017, 2021, and 2022, the Best Family Physician Rancho Cucamonga award in 2019, and Patient Choice Awards for Family Doctor from 2014 through 2018. " He is passionate about healthy behaviors and preventive care. Outside medicine, he enjoys golf and fitness.
Education & Training
Undergraduate
University of San Diego, BA Chemistry, 1982
Medical School
Loyola Stritch School of Medicine, Maywood, IL, Doctorate of Medicine, 1986
Residency
San Bernardino County Medical Center, Family Medicine, 1987-1989
Additional Training
Internship: San Bernardino County Medical Center, 1986-1987
Certifications
Conditions Treated
Who is Dr. Fagan right for?
Dr. Fagan is a strong fit for adults seeking a long-term primary care physician with deep preventive medicine expertise. Older adults and those managing complex, chronic conditions benefit from his geriatric specialization. Patients who want proactive health monitoring will find value in his advanced cardiac, cognitive, and metabolic screening. His direct cell phone access and same-day availability suit patients who prioritize reliable, unhurried care.
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Frequently Asked Questions
Dr. Fagan treats a wide range of conditions across family medicine and geriatrics. His focus includes chronic disease management, cardiovascular risk, metabolic and nutritional concerns, cognitive health, and age-related conditions. He also emphasizes preventive care to catch health issues early.
Yes. Dr. Fagan holds certification as a Diplomate of the American Board of Family Medicine. He also carries a Certificate of Added Qualification in Geriatrics, making him dually certified in both specialties.
Dr. Fagan earned his medical degree from Loyola Stritch School of Medicine in Maywood, Illinois in 1986. He completed his internship and family medicine residency at San Bernardino County Medical Center, finishing his training in 1989.
Dr. Fagan has practiced medicine for 35 years. He has served as Medical Director of Aspen Family Medicine and Geriatrics since 2013 and maintains affiliations with San Antonio Regional Hospital and Casa Colina Hospital and Centers for Healthcare.
Dr. Fagan has earned Top Doctor honors in 2009, 2012, 2015, 2017, 2021, and 2022. He also received the Best Family Physician Rancho Cucamonga award in 2019 and Patient Choice Awards for Family Doctor each year from 2014 through 2018.
Yes. Dr. Fagan holds a Certificate of Added Qualification in Geriatrics alongside his family medicine board certification. That dual training gives him particular depth in caring for older adults with complex or multiple medical needs.
Dr. Fagan is passionate about preventive medicine and healthy behaviors. He uses advanced diagnostic tools including Cleveland HeartLab heart disease screening, cognitive health assessments, inflammation testing, and a metabolic and nutritional panel to identify risks before they become serious problems.
Yes. Members reach Dr. Fagan directly by cell phone for urgent needs. He is also available by phone after hours and on weekends, giving members consistent access to their physician.
Doctor profile last updated March 21, 2026