Big reasons for the savings:
•Generic drugs. The use of generic drugs has grown sharply, especially among seniors. Norvasc, for high blood pressure, and Fosamax, for osteoporosis, are among expensive drugs now available in generic form. Generics account for 64% of Medicare prescriptions compared with 61% in the private sector, Medicare says.
•Fewer enrollees. The program has 2 million fewer participants than originally forecast. Some seniors decided to keep existing drug coverage, Medicare says. Also, fewer poor people enrolled than expected.
•Doughnut hole. Seniors have cut costs to avoid falling into the "doughnut hole" — a coverage gap in which drug expenses between $2,510 and $4,050 a year are not insured.