The new rules say states cannot select one Medicare drug plan and enroll all their beneficiaries in that plan.
The G.A.O. has found that seniors receive accurate and complete information from Medicare drug plans only one-third of the time.
Most Medicare drug plans have a coverage gap (also called the "donut hole").
Our seniors were promised that the new federal Medicare drug plan would make it easier and cheaper to obtain their medication.
Industry executives argue that the proposed Medicare drug benefit will, on its own, help bring drug prices down.
The established companies say the Clinton proposal for rebates on Medicare drugs is especially worrisome.
The move amounts to an offer to compromise with a Senate plan to give the same Medicare drug benefits to everybody.
Blue Cross and Blue Shield officials said their plans had received contracts to provide free-standing Medicare drug coverage in 41 states.
The Congressional Research Service estimates that drug benefits under that plan are worth about 50 percent more than the proposed Medicare drug benefits.
United already planned to offer Medicare drugs in partnership with Walgreens - both in stores and by mail.