Little Feat, Viagra, and Autonomy

So, I'm driving into work singing along with a '78 Little Feat show and the chorus to Old Folks' Boogie catches me:

And you know that you're over the hill
When your mind makes a promise that your body can't fill
Old folks boogie
And boogie we will
'Cause to us the thought's as good as a thrill

Of course, this was written before certain pharmaceutical advances. I figured they'd have to rewrite the words:

You know you ain't over the hill
As long as you get a little blue pill.
Old folks boogie
And boogie we will
'Cause Pfizer given us a chance at a thrill.

On a more serious note, it does raise some interesting autonomy questions. Given that we have a number of older people in assisted living facilities and means to allow some, who previously could not, to remain sexual, how much autonomy should be granted concerning the use of these drugs?

This is not a question of privacy. Surely consenting adults should be able to do what they choose in their home, even if it is a shared home as long as they are not intruding on the rights of their neighbors. But what happens when it becomes a question of safety? Suppose there are concerns about side effects or mixed medicines? Suppose there is concern about the health of a man's heart and the effects of the drug? These are adults, not children, but at the same time the facility does seem have some responsibility for the medical well-being of its residents. Is it a different question if it is not a pharmaceutical matter, but simply fear on the part of a physician for the strength of the bones of someone with osteoporosis? Humans are sexual beings, it is a part of a well-lived human life, but how far may concern for the well-being of another or professional obligations intrude upon the autonomy of a person to make a personal decision like this?