Eric S. Leith


Dr. Eric Leith


Eric S. Leith, MD, FACP, FAAAAI, FRCPC, is a specialist in internal medicine, and allergy and immunology at Cleveland Clinic Canada. Dr. Leith is also a staff physician at Oakville Trafalgar Memorial Hospital, Women’s College Hospital and Sunnybrook Health Sciences Centre. Dr. Leith is a lecturer in the Department of Medicine at the University of Toronto and practices Clinical Immunology, Allergy and Internal Medicine in the Greater Toronto Area (GTA). Dr. Leith is certified by the Royal College of Physicians and Surgeons of Canada with Fellowships in Clinical Immunology (FRCPC) and Internal Medicine (FRCPC).

Dr. Leith completed his undergraduate studies at McMaster University, his medical studies at the Royal College of Surgeons in Ireland and his Internship at McMaster University. Dr. Leith completed his postgraduate training in Internal Medicine at McGill University, and sub-specialty training in Clinical Immunology at the University of Toronto, then served as Chief Medical Resident in Internal Medicine at St. Michael’s Hospital.

Published in peer-reviewed journals and highly respected for his expertise, Dr. Leith leads and has lead numerous positions in the field of Clinical Immunology. Dr. Leith is the Past President of both the Canadian Society of Allergy and Clinical Immunology, and the Allergy Asthma Immunology Society of Ontario where he currently serves at both organizations in the Executive position. He is the Chair of The Canadian Allergy Asthma and Immunology Foundation (CAAIF) and has recently served on the Board of Directors of AllerGen NCE. He is a lead peer assessor for Allergy and Clinical Immunology at The College of Physicians and Surgeons of Ontario and he is a Medical Advisor for Anaphylaxis Canada. Dr. Leith is a member of the Department Advisory/Appointments Committee of the Department of Medicine, University of Toronto. Dr. Leith is an honoured recipient of the Laureate Award from the American College of Physicians, Ontario Chapter.

In his free time, Dr. Leith enjoys spending time with his family, reading, theatre, travelling, and playing sports.


University of Toronto
Clinical Immunology
Toronto, ON
McGill University
Internal Medicine
Montreal, QC
McMaster University
Faculty of Medicine
Hamilton, ON
Doctor of Medicine
Royal College of Surgeons in Ireland (RCSI)
Dublin, Ireland
Bachelor of Sciences
McMaster University
Hamilton, ON


  • Fellow of the America College of Physicians (FACP)
  • Fellow of the American Academy of Allergy Asthma and Immunology (FAAAAI)
  • Fellow of the Royal College of Physicians and Surgeons of Canada in Clinical Immunology (FRCPC) 
  • Fellow of the Royal College of Physicians and Surgeons of Canada in Internal Medicine (FRCPC)

Specialty Interests

  • Internal Medicine
  • Allergy and Clinical Immunology

Awards and Honours

  • Laureate Award, 2011
  • American College of Physicians, Ontario Chapter

Professional Memberships

  • Royal College of Physicians and Surgeons of Canada
  • Canadian Society of Allergy and Clinical Immunology
  • Ontario Medical Association
  • Ontario Allergy Society/Allergy, Asthma and Immunology Society of Ontario
  • American Academy of Allergy and Immunology
  • American College of Physicians