A study of opioid-dependent patients entering drug-treatment programs across the country finds oxycodone is the most popular prescription opioid to abuse because of the quality of the high the drug produces.

Overall, 75 percent of people who abuse prescription opioids use either oxycodone or hydrocodone, Science Daily reports. The study of 3,520 people who abused opioids found 44.7 percent of patients preferred oxycodone, while 29.4 percent preferred hydrocodone. Ninety percent said they used opioids to alter their mood, while 50 of oxycodone users and 60 percent of those using hydrocodone said they also used the drugs to treat pain.

The findings are published in the journal Pain.

“The data show that hydrocodone is popular because it is relatively inexpensive, easily accessible through physicians, friends, and families, and is perceived as relatively safe to use, particularly by risk-averse users,” researcher Theodore J. Cicero, PhD, of the Department of Psychiatry at Washington University in St. Louis, said in a news release. “This group includes generally risk-averse women, elderly people, non-injectors, and those who prefer safer modes of acquisition than dealers, such as doctors, friends, or family members. In contrast, we found that oxycodone is much more attractive to risk-tolerant young male users who prefer to inject or snort their drugs to get high and are willing to use riskier forms of diversion despite paying twice as much for oxycodone than hydrocodone.”

The researchers noted people who abuse oxycodone are more likely to tamper with the drug in order to inhale or inject it, compared with those who use hydrocodone. While the introduction of an abuse-deterrent formulation of OxyContin in 2010 led to a significant decrease in abuse of the drug, oxycodone products remain more popular than hydrocodone products among people who abuse opioids, they said.