Brief

In the world of pharmacovigilance (PV), adverse drug reactions (ADRs) and adverse events (AEs) hold separate definitions. These two terms are not synonymous to each other. However, to draw comparisons, an AE is somewhat a more general term that means any untoward reaction an individual experiences after taking medication. An ADR on the other hand is a more specific term and this reaction is usually qualified by circumstances that show that the untoward/unwanted reaction has a causal relationship with the medication taken.

To illustrate ADRs and AEs, we take a case of a patient who took drug X in the morning for pain and a few hours later was involved in a road traffic accident. In this case, we consider the road traffic accident as an AE until qualified otherwise. On the other hand, a patient who took drug X in the morning for pain and three hours complained of slight dizziness. Since he took drug X from a new pack he had opened, he assumed it was something else he ate and disregarded the dizzy spell and drove his car to attend a meeting. Three kilometers away from the start of his journey, he became unconscious while driving and was involved in a road traffic accident. This incidence should be considered to be as a result of an ADR.