A Mississippi jury awarded $150 million in actual damages to five people who claimed their health problems could be traced to the controversial diet drug cocktail known as fen-phen. The jury verdict against American Home Products Inc. could kill its planned merger with Warner-Lambert Co., which has received a higher bid from Pfizer Inc. Jurors were still determining punitive damages late Tuesday. The trial, which began last month in Fayette, Miss., a rural community of about 2,000, could have a major impact on a proposed national settlement of thousands of lawsuits over the drug combination alleged to cause heart and lung damage, because it could motivate other diet drug users to opt out of the settlement so they can sue on their own. American Home Products issued a statement saying it will appeal the verdict. The plaintiffs contend the drug combination left them with a lung disorder known as pulmonary hypertension. The plaintiffs sought $130 million: $25 million each for four of the plaintiffs and $30 million for the fifth and youngest, a 25-year-old woman. About 6 million people took the mix of fenfluramine and phentermine after it became available in the mid-1990s. American Home withdrew the drugs from the market in 1997 after a Mayo Clinic study linked fen-phen to potentially fatal heart valve damage. American Home agreed earlier this year to pay up to $4.83 billion in a settlement that could cover all 6 million users.