What is a “Black Box” Warning?

A “black box” warning (sometimes called “black label” or “boxed” warning) is a type of warning that appears on prescription drugs that may cause serious adverse effects. Its name refers to the black border that usually surrounds the warning.

A black box warning means that medical studies indicate that the drug carries a significant risk of serious or even life-threatening adverse effects. The U.S. Food and Drug Administration (FDA) can require a pharmaceutical company to place a black box warning on the drug's labeling, advertising and literature. It is the strongest alert the FDA can require.

Even though the bold warning label is printed on the manufacturer’s wholesale packaging, patients may never see a drug’s “black box” risks.