FDA Adverse Event Reporting System (FAERS) Essentials: A Guide to Understanding, Applying, and Interpreting Adverse Event Data Reported to FAERS

The US Food and Drug Administration (FDA) performs safety assessments throughout the life cycle of a drug. Postmarketing safety surveillance promotes the identification of adverse events not known at the time of approval. Adverse event reports, also called individual case safety reports (ICSRs), submitted to FDA, are collected and stored in the FDA Adverse Event Reporting System (FAERS). ICSRs stored in FAERS may be reviewed—along with multiple other data sources—to detect potential safety signals and to perform a thorough evaluation to determine if a causal association exists between a drug and an adverse event. Although FAERS is a powerful tool for drug safety surveillance and assessment, understanding the content, application, and proper interpretation of the data contained in FAERS is necessary to reach scientifically and medically accurate conclusions and contextualize findings. This article aims to highlight considerations and explain fundamental concepts of FAERS to promote accurate analyses and appropriate interpretation of the data available.