The average monthly premium for Medicare Part D prescription drug coverage will increase slightly over the previous two years, the Centers for Medicare & Medicaid Services said last week.

Average premiums through stand-alone prescription drug plans will be about $25 in 2008. Still most beneficiaries can choose plans with premiums less than $20, CMS said. Some plans will feature a $0 deductible and some will include generic drug coverage in the so-called doughnut hole for less than $30.

Plan-specific details will be released publicly in mid-October in advance of the Nov. 15 start of open enrollment. Open enrollment for 2008 runs through Dec. 31.

For information on state-by-state plan offerings visit http://www.cms.hhs.gov/center/openenrollment.asp.