Following the lobbying and efforts of a number of individual physicians and the Ontario Hospital Association (OHA), in 1979, the Ontario Minister of Health, allotted specific funding for the establishment of two provincial poison information centres as centres for excellence in the care of the poisoned patient. These two regional centres employed specialized nurses trained and qualified in the care of the poisoned patient. Since the closure of one of these regional centres in November 2005, only the centre in Toronto remains. Here specialized nurses and pharmacists receive phone consultations in both official languages 24 hours a day, 365 days per year from across the province and offer advice and information to families, caregivers, teachers, law enforcement personnel, and health care providers at all levels. From 1979, when the first Specialists in Poison Information (SPI) and the first Medical Director were hired, calls managed by the Poison Information Centre have increased from approximately 15,000 to 90,209 in 2005.  

In the March 2007, the centre launched a rebranding and social marketing campaign to advertise our name change to the Ontario Poison Centre (OPC) and to increase awareness of our services.