"In 2004, 6.0 million persons were current users of psychotherapeutic drugs taken nonmedically (2.5 percent). These include 4.4 million who used pain relievers, 1.6 million who used tranquilizers, 1.2 million who used stimulants, and 0.3 million who used sedatives. These estimates are all similar to the corresponding estimates for 2003.
"There were significant increases in the lifetime prevalence of use from 2003 to 2004 in several categories of pain relievers among those aged 18 to 25. Specific pain relievers with statistically significant increases in lifetime use were Vicodin®, Lortab®, or Lorcet® (from 15.0 to 16.5 percent); Percocet®, Percodan®, or Tylox® (from 7.8 to 8.7 percent); hydrocodone products (from 16.3 to 17.4 percent); OxyContin® (from 3.6 to 4.3 percent); and oxycodone products (from 8.9 to 10.1 percent)."


Substance Abuse and Mental Health Services Administration, Results from the 2004 National Survey on Drug Use and Health: National Findings (Rockville, MD: US Dept. of Health and Human Services, Office of Applied Studies, 2005), p. 1.