Adverse Drug Reactions (ADR) and Adverse Events (AE)

An adverse drug reaction (ADR) refers to an adverse physical episode following consumption of a medication. These reactions may occur acutely or chronically and can result from interactions with multiple medications. An adverse event (AE) is any negative medical occurrence that is associated with the use of a medication or a medical error. An AE can be life-threatening. An ADR differs from an AE in that an ADR is associated with a causational relationship between the medication and the injury. Within AEs, such events are viewed as side effects and causative relationships between a drug and the event cannot be established. AEs can also be related to medical procedures.