The press hailed it as a victory for patients. People harmed by drugs can sue the manufacturers, the Supreme Court recently ruled, even when the firms have scrupulously complied with all FDA rules.

But the decision will prove to be a pyrrhic victory for patients. In the long run it will hurt countless thousands desperately needing innovative drug treatments.

In dissent, Justice Samuel Alito pointed out that the case, Wyeth v. Levine "illustrates that tragic facts make bad law." The tragedy was that Diana Levine, a musician in Vermont, lost her arm due to gangrene after a physician's assistant injected her with Phenergan, an anti-nausea drug made by Wyeth that's been on the market since 1955. The assistant ignored no fewer than six warnings on the drug's FDA-approved label, stating that injection into an artery could cause gangrene and that the use of an IV heightened the risk of mis-injection. (The assistant also injected twice the maximum labeled dosage and ignored Levine's complaints of extreme pain, which the label stated indicated injection into an artery.)

Quite appropriately, Levine collected damages for medical malpractice from the clinic and the medical practitioners who caused her injuries.

But then she sued Wyeth claiming that the warnings on the drug's label were not enough, that IV administration should have been contra-indicated -- that is, eliminated -- as a means of injection. Wyeth argued that it should not be liable to state tort actions when its label clearly and succinctly warned about the dangers of misuse in language approved by the FDA, the agency charged by federal law with determining the safety of drugs marketed to the American public. A Vermont jury awarded Levine $7.4 million.

In affirming that decision, the Supreme Court has opened up pharmaceutical companies to being whipsawed "with 50 (or more) potentially conflicting rules," Alito noted. In effect, the ruling leaves tort juries in every state "rather than the FDA...ultimately responsible for regulating warning labels for prescription drugs."

The long-term result: fewer innovative drugs will be brought to market. If federal approval no longer protects drug companies from lawsuits, the already enormous costs of developing, testing, and marketing new drugs will rise even higher. Drug makers will have no choice but to pull the plug on potentially beneficial treatments that present too great a legal risk. The patients these drugs would have helped will suffer needlessly.

Indeed, some drugs already helping patients with severe health problems may get pulled off the market. That's likely if even a very small number of users suffer side effects that will allow them to file costly tort claims against the manufacturers. Sure, the FDA-approved warning labels made those risks known in advance. But after Wyeth v. Levine, that doesn't much matter. And keep in mind that the potential side effects of some drugs, such as those used for chemotherapy, are much more serious than those associated with Phenergan. This case opens up potential liability for some of the most effective drugs developed in recent years to treat serious, debilitating illnesses.

It has happened before. Runaway litigation has drastically reduced the number of anti-nausea drugs available to U.S. patients, even though European health care systems use them with few negative consequences. Patients who would have benefited most -- but have been denied relief -- include those with serious conditions like cancer and AIDS.

State juries are simply not equipped to perform the kind of harm-benefit balancing test that the FDA and its experts apply when they examine new drugs. As Justice Alito observed, "Juries tend to focus on the risk of a particular product's design or warning label" for one particular person who may have been injured. They do not look at the overall benefit a particular drug may offer a multitude of patients. The FDA, however, takes the long view. Its drug-approval determinations consider the interests of all potential users including, most importantly, those who would suffer without new medical treatment if "juries in all 50 states were free to contradict" the FDA's expert determinations.

The Supreme Court's decision will inevitably lead pharmaceutical firms to pull drugs off the market, particularly those developed for relatively small populations of sufferers. The risk of tort liability suits in 50 different states will be too great to keep selling many of them. And that risk, no doubt, will stifle the development of new drugs for a wide variety of diseases.

That's a tragedy that will long overshadow what happened to Ms. Levine. This "bad law" will lead to many more tragic facts.

Hans A. von Spakovsky is a visiting legal scholar at the Heritage Foundation. He is also a former commissioner on the Federal Election Commission and counsel to the assistant attorney general for civil rights at the Department of Justice.