U.S. Pharmacopeia, the independent drug-standards agency that will help decide what drugs to cover, has included "impotence agents" on its draft list of recommended drug classes for the benefit, which begins in 2006. 

Critics say the drugs' possible inclusion, while popular among seniors, isn't medically warranted and will increase the new drug benefit's cost, projected to reach $534 billion by 2014. 

"If you have a certain amount of money that you want to spend on health care for the elderly, how much of a priority is covering these types of pharmaceuticals as opposed to other therapeutic interventions? I think most experts would put these types of [drugs] fairly far down on the priority list," said Robert Reischauer, president of the Urban Institute, a Washington economic-research group. 

It's unclear what the demand would be among the 65-and-older population if the drugs were available from Medicare for a modest co-payment rather than the current cost of $8 to $10 a pill. 

Researchers at Duke University have found that 80 percent of men in their late 60s remain interested in sex and that one in every four men aged 78 and older is sexually active. 

A drug to increase sexual desire in post-menopausal women also might be covered under Medicare if the Food and Drug Administration approves the sale of a female testosterone patch developed by Procter & Gamble and Watson Pharmaceuticals. Roughly 24 million of Medicare's 42 million enrollees are women. 

Medicare officials say it's too soon to say what drugs will be covered. U.S. Pharmacopeia has until Dec. 31 to submit its final draft of recommended drug classes. Medicare is expected to finalize the list early in 2005.