Riding the rollercoaster: the ups and downs in out-of-pocket spending under the standard Medicare drug benefit.

This study projects how much Medicare beneficiaries who sign up for the standard Part D drug benefit in 2006 will pay in quarterly out-of-pocket payments through 2008. In the first year we estimate that about 38 percent of enrollees will hit the benefit's no-coverage zone, known as the "doughnut hole," and that 14 percent will exceed the catastrophic threshold. Because drug spending is highly persistent over time, beneficiaries who experience the biggest gaps in coverage are likely to do so year after year, with potentially serious financial consequences.