Oxycodone hydrochloride (HCl) 20 mg IV and naltrexone HCl 2.4 mg IV administered simultaneously x 1 dose IV push over 4 min.

Oxycodone HCl 20 mg for injection x 1 dose IV push over 4 min.

High VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Take Drug Again VAS is a subjective assessment of the degree to which a participant would desire to take the drug again if given the opportunity. It is presented on a 100-point bipolar VAS with score ranging from 0 mm to 100 (score of 0 =

Overall Drug Liking VAS assesses the participant's global perception of drug liking (that is, effects over the whole course of the drug experience including any carryover effects). A 100-point VAS is used to assess response based on a score ranging from 0 to 100 (0 =

Any Drug Effects VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Good Drug Effects VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Bad Drug Effects VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Feel Sick VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Nausea VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Sleepy VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Dizzy VAS assesses the effect experienced by the participant on a 100-point unipolar VAS, where responses are unidirectional and range from a response of 'none' (score of 0) to 'extremely' (score of 100).

Pupillometry assessments measured change in pupil size (miosis) as an indicator of opioid pharmacological properties. The same eye for each participant was used for all measurements during the study. Participants have the size of their pupil measured (in mm) using a pupillometer. Measurements are made in a dimly lit (mesopic) room with controlled lighting conditions.

Plasma decay half-life is the time measured for the plasma concentration to decrease by one half.

AUC is a measure of the plasma concentration of the drug over time.

CL is a quantitative measure of the rate at which a drug substance is removed from the body.

Volume of distribution is defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired blood concentration of a drug. Steady state volume of distribution (Vss) is the apparent volume of distribution at steady-state.