Guidelines

How is oxycodone metabolised and excreted?

How is oxycodone metabolised and excreted?

Oxycodone is extensively metabolized in the liver and only ca. 10% of the dose is excreted unchanged in urine in adults (Pöyhiä et al., 1992; Kirvelä et al., 1996; Lalovic et al., 2006), but the majority of the metabolites are excreted in urine (Lalovic et al., 2006).

What is bioavailability of oxycodone?

Oxycodone has high bioavailability, 60%, when compared with morphine, which has a bioavailability of 33%, thus making oxycodone almost twice as potent as morphine.

What enzyme metabolizes oxycodone?

Oxycodone is primarily metabolized in the liver by the cytochrome P450 (CYP) enzymes with CYP3A as the major metabolic pathway and CYP2D6 as the minor metabolic pathway to noroxycodone, oxymorphone and noroxymorphone. Oxycodone exerts its analgesic effect via the µ-opioid receptor.

What does a 10 panel test for?

Standard 10-panel test: typically looks for cocaine, marijuana, PCP, amphetamines, opiates, benzodiazepines, barbiturates, methadone, propoxyphene, & Quaaludes.

How quickly is oxycodone absorbed?

In normal volunteers, the t½ of absorption is 0.4 hours for immediate-release oral oxycodone.

How many total stereoisomers does oxycodone have?

The molecular structure of oxycodone contains two planar rings, two aliphatic rings and four chiral centers. Oxycodone molecules can form up to 16 stereoisomers and are not highly lipophilic [1, 5].

What chemicals are used to make oxycodone?

The chemical formula is 4, 5α-epoxy-14-hydroxy-3-methoxy-17-methylmorphinan-6-one hydrochloride. Oxycodone is a white, odorless crystalline powder derived from the opium alkaloid, thebaine. Oxycodone hydrochloride dissolves in water (1 g in 6 to 7 mL).

Where are opiates metabolized?

Opioid metabolism takes place primarily in the liver, which produces enzymes for this purpose. These enzymes promote 2 forms of metabolism: phase 1 metabolism (modification reactions) and phase 2 metabolism (conjugation reactions).

How is oxycodone metabolized in the liver?

Oxycodone is metabolized in the liver by Phase I and Phase II metabolism. Phase I metabolism occurs through the cytochrome P450 (CYP450) enzymes 3A4 and 2D6 to nor-oxycodone and oxymorphone, respectively (see Figure).

Which is a Phase 1 metabolite of oxycodone?

Oxycodone Metabolism. Phase I metabolism occurs through the cytochrome P450 (CYP450) enzymes 3A4 and 2D6 to nor-oxycodone and oxymorphone, respectively (see Figure). Oxymorphone is a minor metabolite, which represents less than 15% of the total administered dose, but certainly is an expected byproduct of oxycodone.

Which is a better metabolite oxycodone or oxymorphone?

Although oxymorphone is considered a minor metabolite of oxycodone, immunoassay urine drug screening of patients treated with oxycodone can be expected to be positive for oxymorphone. Further, the quantity of oxymorphone (determined by GC/MS) can at times equal or exceed that of oxycodone.

What kind of receptor does oxycodone bind to?

Oxycodone, an synthetic opioid, is a highly selective full agonist of the μ-opioid receptor (MOR). This is the main biological target of the endogenous opioid neuropeptide β-endorphin. Oxycodone has low affinity for the δ-opioid receptor (DOR) and the κ-opioid receptor (KOR), where it is an agonist similarly.