What class of drugs are OxyContin and oxycodone?

Which of these are sometimes called “study drugs” by teens and young adults who sometimes use them to stay up to study longer for exams?

What drug is most often seen in overdose cases in the emergency room?

The use of these drugs tripled among young adults and college students between 1998 and 2006:

Which of these prescription drugs are particularly dangerous to take with alcohol?