Now more than ever it’s crucial to have a strong backup defense. That’s what pharmaceutical companies are learning after a Supreme Court decision that shot down pre-emption as a defense in many cases where plaintiffs claim prescription-drug warnings are inadequate.

While the court’s March ruling in Wyeth v. Levine stripped the defendants’ arsenal of a primary weapon, it did not render drug manufacturers defenseless. Recent 5th Circuit decisions in Ebel v. Eli Lilly & Co. and Allgood v. GlaxoSmithKline, echoing similar rulings in other jurisdictions, have reinforced an old standby–the learned intermediary doctrine–as a prime litigation spoiler.