THE CAMPAIGN of Sen. John F. Kerry (D-Mass.) has put out a statement showing that the prices of drugs offered to holders of the administration's new prescription discount cards for the elderly are actually higher than the prices of drugs posted on the Web site Drugstore.com. But other studies appear to show that the cards are beneficial, particularly to low-income seniors. The differences are easily explained: Prices depend on where people live, what drugs they use, what cards they choose, their income -- special deals are available to those with lower incomes -- and whether they are willing to shop online. More to the point, a comparison of the least effective drug cards with the best Web prices looks very different from a comparison of the most effective drug cards with ordinary retail prices.

But if that is the case, how are ordinary seniors to know which card, if any, is best for them? Even those who support the cards agree that information about them has been confusing. During a tour this week to promote the cards in the Midwest, the president acknowledged that "we've got some problems" with the program. Poor communication between Medicare bureaucrats and the Agriculture Department made it seem, earlier this month, as if low-income seniors would have to give up food stamps to take advantage of a $600 discount they receive with the cards. That problem has been eliminated, but enrollment in the program remains low, largely because too many people are unaware of the cards or uncertain how to evaluate them. Users complain that the government's help line, 1-800-Medicare (800-633-4227), requires long waits and conversations with computerized voices. They also say that the Web site, at www.medicare.gov, even after initial hitches and incorrect data were fixed, remains difficult to use.

The real complications, however, are created not by technology but by the design of the program itself. It isn't clear, for example, why drug companies are allowed to change their prices throughout the year, though it is true that prices have so far only fallen. It isn't clear why seniors are locked into the card they choose for a year. Above all, it isn't clear why a program as complicated as this one had to be implemented in six months. If these cards were worth doing -- if, that is, they were not merely a pre-electoral ploy -- it was worth thinking all of these issues through and preparing the public. Those planning to implement the permanent drug discount program in 2006 should take this as a lesson. Whatever the politics, nothing as complicated as a prescription drug program should be wheeled out too early.