Inpatient Medicine Consult Service & Extensivist Clinic
Southlake Regional Health Centre
Newmarket, Ontario, Canada

Dr. Nathanson completed his medical degree and internal medicine training at the University of Toronto Faculty of Medicine and has been practising internal medicine and critical care medicine at Southlake Regional Health Centre in Newmarket, Ontario since 1995. In 2010, he earned a Master of Science in Health Care Management from the Harvard Graduate School of Public Health. He is currently pursuing graduate studies in Medical Bioethics and Jewish Health Law at the Rabbi Isaac Elchanan Theological Seminary of Yeshiva University in New York.

Throughout his career, Dr. Nathanson has held numerous administrative and leadership roles at Southlake, including Medical Director of the Inpatient Palliative Care Unit, founding Medical Director of the Heart Function Program, President of the Medical Staff Association, Chair of the Clinical Quality and Resource Utilization Committee, and Medical Director of Acute Medicine Programs. He was instrumental in founding the Clinical Resource Utilization Management Program, establishing and equipping the Southlake Simulation Lab, and designing and launching the Southlake Hospital Medicine Program.

Dr. Nathanson has contributed to health policy at the provincial level, serving on two Ontario task forces focused on hospital resource utilization. During the COVID-19 pandemic—from January 2020 through mid-2022—he served as Medical Director of the Intensive Care Unit at Southlake, where he founded the physician-led Critical Care Outreach Program; concurrently held the role of Chief of Staff at Stevenson Memorial Hospital in Alliston, Ontario; and advised local, regional, and provincial pandemic policy panels.

Dr. Nathanson remains actively engaged in medical education, mentoring senior residents through the transition to independent practice. His current clinical work is focused on the inpatient Medicine Consult Service and the Southlake Extensivist Clinic. He also maintains a busy practice as an expert witness in medical malpractice litigation.

Outside of medicine, Dr. Nathanson spends his Canadian winters in the southern United States. He is an avid cyclist and motorcyclist, and enjoys exploring Ontario, the United States, and beyond alongside his wife, Genny.