On June 23, 2011, in a 5-4 decision, the Supreme Court held that federal law preempts state law failure-to-warn claims against generic pharmaceutical manufacturers. Pliva, Inc. v. Mensing, No. 09-993 (June 23, 2011). The sweeping ruling will likely absolve generic manufacturers from liability on virtually all failure-to-warn claims.

Mensing involved the generic medication metoclopramide (brand name Reglan®). The plaintiffs in the trial courts below brought failure to-warn claims against the generic manufacturers whose products they took, claiming that the defendants failed to warn that long-term use of the product could cause in a condition called tardive dyskinesia. The defendants in the respective cases won dismissal based on federal preemption. On appeal and after the Supreme Court’s decision in Wyeth v. Levine, 555 U.S. 555 (2009), which held that federal law does not preempt state law failure-to warn claims involving brand-name drugs, the Fifth and Eighth circuits reversed the judgments. The manufacturers petitioned for certiorari, and the Supreme Court granted review and consolidated the cases.