Adverse reaction (AR)

In Safety & pharmacovigilance

Also known as: adverse drug reaction, ADR

An adverse reaction is an adverse event for which there is at least a reasonable possibility that the study treatment caused it. The difference from an adverse event is the causal judgment. That judgment is normally made by the investigator, and the sponsor may add its own assessment.

Turn the vocabulary into a career

The free CRLN Career Finder maps your background to a clinical-research role and builds a step-by-step roadmap. No cost, no card.

Educational reference only. Where regional rules differ, follow the regulation and the written procedures that apply where you work.