18th March 2024

Overview

Adverse Drug Reactions (ADRs) can be defined as “an appreciably harmful or unpleasant reaction, resulting from an intervention related to use of the medicinal product, which predicts hazard from future administration and warrants prevention or specific treatment, or alteration of drug regime or withdrawal of the product.” Important aspects to consider when labelling a reaction as an ADR include a causal relationship between the medication and the effect (which can be difficult to establish, particularly in the context of polypharmacy) and that the effect observed resulted from a dose which is considered safe in humans.

The effects of ADRs are significant at both an individual and organisation level: 6-7% of hospital admissions are related to ADR. The term “pharmacovigilance” relates to the accountability of healthcare professionals to monitor the safety of medications; in the UK the Medicines and Healthcare products Regulatory Agency (MHRA) and the Commission on Human Medicines (CHM) is ultimately responsible. Clinicians should be familiar with the process for reporting concerns and ADRs, specifically via the Yellow Card Scheme.