DR. THOMAS FRIEDEN, CENTERS FOR DISEASE CONTROL AND PREVENTION:

Doctor, with so much attention being paid to heroin and opioid abuse in the recent years, why are we seeing such is alarming statistic? Really, there are two driving forces. First, doctors are prescribing way too many opioids, for too many conditions, for too long, for too many patients. And this is a major problem.

Second, there's been a flood of illegal opioids, not only heroin, but also synthetic fentanyl and drugs that are inexpensive and widely available.

And those two things are making a very difficult problem continue to get worst.