Articles: oxycodone-pharmacokinetics.
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of the pharmacokinetics of oxycodone administered in three Percocet formulations.
This randomized, open-label, three-period crossover study compared the single-dose pharmacokinetics of three dose levels of oxycodone in combination with acetaminophen (5 mg/325 mg, 7.5 mg/500 mg, or 10 mg/650 mg) in healthy volunteers. Serial 24-hour blood samples were collectedfrom 23 fasting subjects after drug administration. The individual dose levels were evaluated on 3 different days, which were separated by washout periods of at least 7 days, in each subject. ⋯ Only dizziness occurred in a dose-related manner. Increasing dose levels of oxycodone/acetaminophen provides proportional increases in oxycodone Cmax and AUC. Adverse events were predictable based on the opioid pharmacologic actions of this agent.
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Randomized Controlled Trial Comparative Study Clinical Trial
Morphine or oxycodone in cancer pain?
Oxycodone is an opioid analgesic that closely resembles morphine. Oxymorphone, the active metabolite of oxycodone, is formed in a reaction catalyzed by CYP2D6, which is under polymorphic genetic control. The role of oxymorphone in the analgesic effect of oxycodone is not yet clear. ⋯ Liver dysfunction affected selectively either oxycodone or morphine metabolism. Three patients with markedly aberrant plasma opioid concentrations are presented. Significant individual variation in morphine and oxycodone metabolism may account for abnormal responses during treatment of chronic cancer pain.
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Clin. Pharmacol. Ther. · Dec 1998
Randomized Controlled Trial Clinical TrialEffects of blocking CYP2D6 on the pharmacokinetics and pharmacodynamics of oxycodone.
Oxycodone is metabolized in the liver by means of O-demethylation to form oxymorphone in a reaction catalyzed by the enzyme cytochrome P450 2D6 (CYP2D6). This enzyme is expressed as 2 phenotypes (extensive and poor metabolizers). Several drugs are metabolized by CYP2D6, and clinically relevant drug interactions may occur. The aim of this study was to evaluate the role of oxymorphone in mediating the opioid effects of oxycodone by means of blocking CYP2D6 with quinidine. ⋯ A significant reduction in plasma oxymorphone levels did not substantially alter the pharmacodynamic effects of oxycodone. Analgesia was not evaluated because pain was not present.
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J Pain Symptom Manage · Feb 1997
Randomized Controlled Trial Clinical TrialA pharmacokinetic/pharmacodynamic study of controlled-release oxycodone.
A single-dose, analytically blinded, randomized, crossover study was conducted in 22 healthy male volunteers to compare the bioavailability of one 20 mg with two 10 mg controlled-release (CR) oxycodone tablets. In addition, pharmacodynamic effects were assessed using both objective and subjective measures for up to 48 hr after dosing. The two treatments were bioequivalent, with comparable rates (Cmax of one 20 mg tablet was 109% of two 10 mg tablets; 90% confidence limits: 98.4%-120%) and extents (AUC0-infinity: 107%; 100%-114%) of absorption. ⋯ Correlations between plasma oxycodone concentrations and most pharmacodynamic measures were significant. The strongest correlations were observed for pupil size (r = -0.53) and subjects' assessment of drug effect (r = 0.53), with changes in plasma concentration accounting for more than 25% of the observed changes in these variables. This study demonstrated bioequivalence of two 10 mg and one 20 mg CR oxycodone tablet, with significant correlation between plasma oxycodone concentrations and pharmacodynamic effects in normal volunteers.
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Br J Clin Pharmacol · Dec 1996
Randomized Controlled Trial Comparative Study Clinical TrialCharacterization and validation of a pharmacokinetic model for controlled-release oxycodone.
1. Oxycodone is a strong opioid agonist that is currently available in immediate-release (IR) formulations for the treatment of moderate to severe pain. Recently, controlled-release (CR) oxycodone tablets were developed to provide the benefits of twice-a-day dosing to patients treated with oxycodone. ⋯ The mean prediction error was 2.7% with a coefficient of variation of 54%. 4. The absorption characteristics of CR oxycodone tablets should allow effective plasma concentrations of oxycodone to be reached quickly and for effective concentrations to be maintained for a longer period after dosing compared with the IR oral solution. The CR dosage form has pharmacokinetic characteristics that permit 12 hourly dosing.