What defines an adverse drug reaction (ADR)?

An adverse drug reaction (ADR) is defined as an unwanted or harmful reaction to a medication. This encompasses a broad category of effects that can occur when a medication is administered, which may range from mild side effects to severe health complications. Understanding ADRs is essential in pharmacology and patient care, as it helps healthcare professionals anticipate potential risks associated with drug treatments and provides insights into patient safety.

The definition focuses on the negative impact that can arise from drug therapy, which is crucial for effective medication management. Recognizing that ADRs can occur in any patient population and are not limited to particular demographics reinforces the importance of monitoring all patients for potential adverse effects, regardless of age or other factors.