The Federal Trade Commission sued to block two drug distribution mega-mergers that, if allowed, would create two corporate giants with control over the bulk of the nation's wholesale prescription drug business. In lawsuits filed in federal court in Washington, the agency sought to block the acquisition of Bergen Brunswig Corp. in Orange by Cardinal Health Inc. of Dublin, Ohio, and San Francisco-based McKesson Corp.'s purchase of AmeriSource Health Corp. of Malvern, Pa. McKesson is the nation's largest drug wholesaler, Bergen Brunswig ranks No. 2, Cardinal No. 3 and AmeriSource No. 4. The FTC contends that the mergers would create higher drug prices for consumers. The agency seeks a preliminary injunction to halt the mergers while it prepares a case to block the deals. The companies said they are considering whether to challenge the FTC. They have agreed to hold off on the mergers, however, until the court matter is resolved, according to the agency's filing. In New York Stock Exchange trading, Bergen shares rose 44 cents to close at $40.56; Cardinal shares rose $1 to $81; McKesson shares added 19 cents to $55.94; and AmeriSource shares gained 25 cents to $59.69.