The U.S. Supreme Court yesterday gave life to two lawsuits faulting Pfizer Inc. and a GlaxoSmithKline P.L.C. unit for failing to warn that their antidepressants might cause suicidal tendencies in adults.

The justices told the U.S. Court of Appeals for the Third Circuit in Philadelphia, which had rejected the suits, to reconsider them in light of last week's Supreme Court decision giving patients more ability to sue drugmakers.

The antidepressant suits are being pressed by relatives of a woman who killed herself after taking Glaxo's Paxil and a man who committed suicide after taking Pfizer's Zoloft.

Glaxo, based in Britain, employs about 1,500 people in Center City and about 3,200 in Upper Merion and Upper Providence. Pfizer, of New York, is buying rival Wyeth, which has facilities in Collegeville and Malvern that employ about 5,000.

The two antidepressant suits, among hundreds that drugmakers have faced, will test the reach of a high-court ruling that upheld a $7 million award against Wyeth over an antinausea drug. Pfizer and GlaxoSmithKline say their case is different because the Food and Drug Administration had specifically considered and rejected the idea of suicide warnings for adults.

"FDA repeatedly determined that the scientific evidence did not support such an association," Pfizer said in a court filing.

The U.S. Court of Appeals agreed, saying the FDA studied the issue for 20 years and concluded that suicide warnings, at least for adults, "are without scientific basis and would therefore be false and misleading."

In 2005 the FDA for the first time required antidepressant packaging inserts to warn doctors and patients about the risk of suicide among children. The agency extended that warning to ages 18 to 24 in 2007.

The justices yesterday also told the appeals court to reconsider its rejection of a false-advertising suit over AstraZeneca P.L.C.'s Nexium anti-ulcer treatment.

The Supreme Court said last week that Congress, in setting up the federal drug-approval system, had intended to allow traditional product-liability suits as an additional layer of protection for consumers.

"Congress did not intend FDA oversight to be the exclusive means of ensuring drug safety and effectiveness," Justice John Paul Stevens wrote for the majority.

Still, the court left open the possibility that product-liability suits would be precluded when they centered on a proposed warning that the FDA had considered and rejected. Stevens said that in the Wyeth case, the FDA hadn't considered whether doctors should be warned not to use a disputed injection method.