Spontaneous adverse drug reaction (ADR) reporting systems are under-utilized worldwide and Canada’s is no exception. However, apart from expensive unique arrangements such as patient registries, they are the only systems regularly available to collect and analyze ADR reports as soon as a new drug receives marketing approval and, in some circumstances, can provide early insight into a safety risk.

Health Canada’s spontaneous ADR reporting system was established in 1965 in the wake of the thalidomide tragedy. Annual summaries of the number of reports received, how many ADRs were “serious,” and the report sources were included in the Canadian Adverse Reaction Newsletter from 1996. The annual summary for 2000, the first to be online, contained additional data on the top 11 drug classes associated with ADRs. Uniquely, the number of ADR reports with a fatal outcome (about 2.7 per cent of the total) was also provided. No other annual summary has included this information.

From 2005, Health Canada began to focus on numbers of patients rather than numbers of ADR reports because multiple reports may be submitted about a patient. Three years later, the number of patients by broad drug category was added to the annual summary. Information about the gender and age of patients with ADRs was included from 2010.

The last annual summary was published in 2013 relating to 53,109 ADR reports received in 2012 of which almost 80 per cent were categorized as “serious,” indicating that severe ADRs are more likely to be reported. The 53,109 reports concerned 36,101 patients of whom nearly 60 per cent were female and more than a quarter were seniors. Most of the reports (69 per cent) came from health-care professionals and 84 per cent were submitted via a pharmaceutical company. The top three drug groups with ADRs were immunosuppressants (anti-rejection drugs), cancer drugs and analgesics.

The reason for the discontinuation of the annual summaries is not known. Although limited, the summary information provided Canadians with a basic understanding of drug safety risks that required little effort to access. Health Canada does have an online search engine that provides information on specific drugs, ADRs or combinations of drugs and ADRs reported since 1965. However, it requires health-care professionals and the public to be aware of its existence and it cannot produce the total number of cases per year.

Use of the search engine reveals that ADR reports are recorded by date of receipt. For example, 313 ADR reports mentioning Vioxx were received in 2004 (the year when the drug was withdrawn) and another 171 were received in 2005. Vioxx-associated ADR reports continue to be received by Health Canada―a fifth of all ADR reports and over 23 per cent of “serious” reports associated with Vioxx were received between 2006 and June 30, 2016 (the latest data available). No information is accessible about the dates when the ADRs occurred, although most undoubtedly occurred years before the reports were received.

The Liberals were elected on a platform that included promises for “open and transparent government making transparency a fundamental principle across the Government of Canada.” Transparency means that information should be available publicly. If openness is a fundamental government principle, annual summaries on ADRs should be reinstituted and expanded to provide more detail such as the date of ADR occurrence, the type of ADR, how the ADR was dealt with and what the outcome was.

Easy to read annual summaries of ADR reports should be publicly available and should also be provided directly to health-care professionals to engage them in supporting the ADR reporting system. Greater understanding of the risks of drugs among health-care professionals and the public is important to educate Canadians about appropriate use of medicines and to allay concerns about drug risks.