Therapeutic disasters that hastened safety testing of new drugs.

New drugs were not required to undergo premarket safety testing in the United States until 1938, when a therapeutic disaster-the Elixir Sulfanilamide tragedy-prompted Congress to pass a bill mandating this now-routine process. History repeated itself nearly 25 years later, when another therapeutic disaster-the thalidomide tragedy-led to passage of new amendments in 1962 to ensure drug efficacy and greater drug safety. As is typical with historical events, critical information was gained that led to novel approaches for understanding, predicting, diagnosing, and managing drug-induced toxicities. Continued refinement of current, along with development of new, approaches will mitigate future drug-related catastrophes, with the goal of avoiding them entirely.