# Boxed Warning (Black Box Warning)

> The strongest safety warning the FDA requires, appearing in a box at the top of a prescription drug's labeling to highlight serious or life-threatening risks.

**Category:** Regulatory
**Canonical URL:** https://drugsmonitor.com/glossary/boxed-warning
**Last updated:** 2026-06-11

Boxed warnings are reserved for drugs with significant risks that may lead to hospitalization or death. They must be prominently displayed at the beginning of the prescribing information. Examples include opioid addiction risk, cardiovascular events, and severe allergic reactions.

The FDA can require a boxed warning based on clinical trial data, post-market adverse event reports, or safety studies. Manufacturers may be required to update existing boxed warnings if new evidence of greater risk emerges.

The presence of a boxed warning does not mean the drug should not be used, but it signals that patients and prescribers should carefully weigh the risks and benefits. Boxed warnings are often key evidence in failure-to-warn litigation.

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*Glossary entry from DrugsMonitor.com.*