Association of Clinical Research Professionals (ACRP) Certified Professional Practice Exam

What is classified as an Adverse Drug Reaction (ADR)?

1. An unintended response to a drug

2. A mild side effect

3. A condition returned to baseline

4. An unavoidable medication error

The correct answer is: An unintended response to a drug

An Adverse Drug Reaction (ADR) is defined as an unintended, harmful response to a drug administered at normal doses for prophylaxis, diagnosis, or treatment. This classification encompasses any negative effects experienced by a patient, which occur as a direct result of the medication. Such reactions may vary in severity, ranging from mild to severe, and can lead to significant health complications. The selection of the first option captures the essence of what an ADR is, delineating it from other drug-related issues such as side effects, which may be mild or expected. Mild side effects, while common, do not always fall under the definition of ADRs since they are often benign and anticipated outcomes of a drug's pharmacological action. Other options address different scenarios unrelated to the precise definition of an ADR. A condition returning to baseline suggests that any prior adverse effects have resolved and thus would not be classified as an ADR at that point. An unavoidable medication error, meanwhile, pertains to mistakes in drug administration rather than the inherent reactions to the drug itself. In summary, the definition of an ADR revolves around the unintended and harmful nature of the drug response, making the first choice the most accurate representation of the term.