Drug makers can be held liable for harm caused by their medicines, even if the drugs already carry federally approved warning labels, the US Supreme Court ruled on 4 March. The high court majority said that Diana Levine was entitled to a US$6.7-million award a state jury gave her, after she sued drug maker Wyeth of New Jersey.

A musician from Vermont, Levine had a Wyeth anti-nausea drug mistakenly injected into an artery, even though a label, approved by the US Food and Drug Administration (FDA), warned against such practice. Gangrene set in, and Levine's forearm was amputated.

The ruling means that FDA labels do not protect companies from liability in state courts, where they are often sued. It could affect many businesses that have sought increased federal regulation as a shield for liability.