Adverse reactions -- what they are, why report and how
What's an adverse drug reaction?
An adverse drug reaction (ADR) is any unintended response to a drug, which includes prescription, non-prescription, biological, and herbal drug products. Drug abuse, drug interactions, and overdoses are also monitored by Health Canada.
When should ADRs be reported?
According to Health Canada, adverse drug reactions should be reported when:
1) The reaction to a drug is unexpected, no matter how severe. This means there is no indication on the labelling or drug information that such a reaction might occur.
2) The reaction is serious. Health Canada defines a serious reaction in the following way:
"A noxious and unintended response to a drug, which occurs at any dose and requires in-patient hospitalization or prolongation of existing hospitalization, causes congenital malformation, results in persistent or significant disability or incapacity, is life-threatening or results in death. Important medical events that may not be immediately life-threatening or result in death or hospitalization, but may jeopardize the patient or may require intervention to prevent one of the outcomes listed above, may also be considered serious."
3) The reaction, regardless of its severity or type, is caused by a drug that has come on the market within the last five years.
Who can report an adverse drug reaction?
Reports can be filed by patients, consumers, doctors, pharmacists, and other health professionals. It is mandatory for pharmaceutical companies to report.
Canada's ADR monitoring program is a voluntary system. It depends on the cooperation of health-care professionals, patients, and consumers to accurately report adverse drug reactions that meet the criteria, set out below. However, pharmaceutical companies are legally bound to report any unexpected adverse reactions to Health Canada.
It is widely acknowledged that there is serious under-reporting of adverse drug reactions (ADRs) in Canada. At the inquiry into the death of 15-year-old Vanessa Young, Health Canada’s Brian Gillespie testified that only about one-in-10 adverse events are reported to the government. Other experts think it's even lower. As a result, it is impossible to project true incidence rates of adverse reactions based on the information captured by CADRIS.
Is all the CADRIS data in this database?
No, this online database does not contain all the data compiled by CADRIS. There are two reasons for this.
1) Before releasing the database to CBC, Health Canada removed certain fields in order to comply with privacy laws. Health Canada removed 11 fields, such as Date of Birth, Date of Death, and Notifier City.
2) In order to prepare this data for the general public, and for ease of access, CBC has streamlined the CADRIS database received from Health Canada.