krantz, chief executive officer and medical director, hanley center, west palm beach, florida; beverly gmerek, prescription drug abuse prevention program coordinator, peer assistance services inc., denver, colorado. dr. clark, how prevalent is prescription drug misuse in the united states? well, we estimate that there are approximately 15 million people who misuse prescription drugs in the united states, and that gives us an estimated 2.5 million new initiates per year, or, if you think about it, that's about 7,000 new initiates a day. and within that, do one age group uses it more than others? what is the distribution among the age groups? well, i think the most important thing to keep in mind is that prescription drug abuse affects the entire age range. we might see some peak use in the 18 to 25-year-olds, but it is a problem that confronts every age range, and what we shouldn't do is to simply dismiss it as a young adult or teenage phenomenon; in fact, it's a problem that affects every age range. dr. krantz, where do most of the nonmedical users of prescription drugs get their drugs? most