"Some of those who develop dependency problems are the patients who get the prescriptions. But many also obtain the drugs illicitly, from a friend, family member or dealer.
Younger people, says Kolodny, may start with prescription medications but then turn to street drugs like heroin because they have "a harder time maintaining their opioid supply by visiting doctors."
Older patients, he says, are less likely to turn to street drugs because they have an easier time getting refills from their doctors.
Data from IMS Health, which tracks prescription drug sales, shows the number of prescriptions for opioid-based drugs have ticked down, falling 11.8 percent from 2012 to 2015. That decline, however, followed a huge increase: The number of opioid prescriptions more than doubled between 2000 and 2012, when more than 282 million prescriptions were written."

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