Subjective, psychomotor, and physiological effects of oxycodone alone and in combination with ethanol in healthy volunteers

Rationale Nonmedical use of prescription opioids is sometimes accompanied by the ingestion of ethanol. Whether ethanol increases the abuse liability-related effects of prescription opioids has not been determined. Objective The purpose of this study was to characterize the subjective, psychomotor, and physiological effects of oxycodone, a widely prescribed and abused opioid, and ethanol, alone and in combination. Methods Fourteen volunteers participated in a randomized, crossover trial in which they were exposed to placebo, oxycodone (10 mg), two doses of ethanol (0.3 and 0.6 g/kg), and oxycodone combined with the lower dose and the higher dose of ethanol on separate sessions. Results Several abuse liability-related subjective effects (drug liking, take again, pleasant bodily sensations) were not increased by the low dose of ethanol or oxycodone alone relative to placebo, but were when the two were combined. Self-reported liking of the higher dose of ethanol was higher than that of placebo, but oxycodone neither increased nor decreased this effect. Psychomotor and cognitive performance was not affected by any of the active drug conditions. Absorption of ethanol was decreased by oxycodone. Conclusions In this study, 10 mg of oral oxycodone combined with a low dose of ethanol generated abuse liability-related effects, but when tested separately, they did not. Further psychopharmacological investigations of this combination are warranted in light of these findings and the fact that nonmedical use of prescription opioids is sometimes accompanied by use of ethanol.