• Progressive ratio breakpoint value [ Time Frame: Post-drug ] [ Designated as safety issue: No ]
  

Prescription opioid abuse is becoming an increasingly widespread and serious public health concern. The 2001 National Household Survey on Drug Abuse report revealed that the number of first-time users of prescription opioid medications for non-medical reasons reached 2 million in the year 2000, a number that has quintupled since 1984. Despite this trend, little experimental research has been directed towards understanding who may be abusing these medications, and under what conditions. The grant will examine the reinforcing, subjective, performance, and physiological effects of two commonly prescribed opioid medications (oxycodone and codeine) in two separate studies. Because it is not clear who is abusing prescription opioids, the medication effects will be compared in drug abusers and non-drug abusers. Additionally, because it is not clear under what conditions these medications are used, the effects of oxycodone and codeine will be examined in the presence and absence of experimentally induced pain. The results of these studies will yield important information about who may be abusing prescription opioid medication, and will provide a better understanding of several important variables that may influence the propensity to abuse these medications.

The following two studies will be performed during the grant period: 1) a study to examine the abuse liability of oxycodone; and 2) a study to examine the abuse liability of codeine. Both studies will include two groups of participants: prescription opioid abusers and non-abusers.