Characterizing the subjective, psychomotor, and physiological effects of oral oxycodone in non-drug-abusing volunteers.
BACKGROUND
The subjective, psychomotor, and physiological effects of a widely prescribed and abused prescription opioid, oxycodone, have not been studied in a population of non-drug-abusing people.


OBJECTIVE
To characterize the effects of oxycodone in non-drug-abusing volunteers.


METHODS
Eighteen volunteers participated in a crossover, randomized, double-blind study in which they received, all p.o., placebo, 10 mg oxycodone, 20 mg oxycodone, 30 mg oxycodone, 40 mg morphine, and 2 mg lorazepam. Measures were assessed before and for 300 min after drug administration. End-of-session and 24-h post-session measures were taken to assess residual drug effects and overall subjects' assessments of the drug effects.


RESULTS
Subjective effects of oxycodone were dose related, with the majority of statistically significant effects limited to the two higher doses tested. Oxycodone produced a profile of subjective effects that included both pleasant and unpleasant effects. Morphine in general produced effects similar in magnitude to those of 10 mg and 20 mg oxycodone. Peak liking and drug-wanting ratings were increased by all doses of oxycodone and by morphine, and trough ratings of liking (dislike) were lower in the 20-mg and 30-mg oxycodone conditions, relative to the placebo condition. Post-session ratings of overall liking and drug wanting were not statistically significant, either at the end of the session or 24 h later. Cognitive and psychomotor impairment were obtained with the higher doses of oxycodone, but to a much lesser degree than that of lorazepam. Miosis and exophoria were increased in a dose-related manner by oxycodone.


CONCLUSIONS
Oxycodone produced effects similar to those of other mu opioid agonists. Although oxycodone produced abuse liability-related subjective effects, it also produced unpleasant effects, a phenomenon we have observed in other opioid studies in non-drug-abusing volunteers.
Zacny
James P
JP
Department of Anesthesia and Critical Care/MC 4028, The Pritzker School of Medicine, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA. jzacny@airway.uchicago.edu.
Gutierrez
Sandra
S
Department of Anesthesia and Critical Care/MC 4028, The Pritzker School of Medicine, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
D000284:Administration, Oral; D000328:Adult; D003071:Cognition / Q000187:drug effects; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004644:Emotions / Q000187:drug effects*; D005260:Female; D006801:Humans; D008140:Lorazepam / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology; D008297:Male; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology; D009294:Narcotics / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D010098:Oxycodone / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D011597:Psychomotor Performance / Q000187:drug effects*; D011795:Surveys and Questionnaires
D009294:Narcotics; D009020:Morphine; D010098:Oxycodone; D008140:Lorazepam