Glucuronide metabolites

Table 2 Cross-reactivity of racemic ractopamine and ractopamine glucuronide metabolites to a monoclonal antibody developed against racemic ractopamine...

CYP2B6 and CYP3A (3A mixed inducer/ inhibitor) 14-34% excreted in urine (glucuronidated metabolites, less than 1 % unchanged) 16-61% in feces... 

Lodi, F, R Jimenez, C Menendez, PW Needs, J Buaret, and E Perez-Vizcaino. 2008. Glucuronidated metabolites of the flavonoid of quercetin do not auto-oxidize, do not generate free radicals and do not decrease nitric oxide bioavailability. Planta Med 74(7) 741-746. 

In a series of studies on 2-amino-A-phenylthiazole (Piscaine), a fish anesthetic, Suzuki and co-workers (24) isolated and identified an N-glucuronide metabolite (2-amino-A-phenylthiazole-2-N-g-mono-D-glucopyranosiduronic acid) from medaka (Oryzias latipes), rainbow trout, and carp (Cyprinus oarpio) (Figure l). 

Korfmacher WA, Holder CL, Betowski LD, et al. 1987. Identification of two glucuronide metabolites of doxylamine via thermospray/mass spectrometry and thermospray/mass spectrometry/mass spectrometry. 

Cui L, Qiu F, Wang NL, Yao XS. (2005) Anew glucuronidated metabolite of andrographolide in hnman. Chin Chem Lett 16 369-371. 

Approximately 16 % of the dose is hydroxylated, 5.8 % at the 5 position (SOH) and 10.2 % at 6 position (SCH2OH). No glucuronide metabolites were formed. Acetylation accounted for 12.7 % of the dose, while the recovery of the parent drug was 13.9 %. Thus approximately 58 % of the administered dose is lost after i.v. application (Table III). The renal clearance of the hydroxy and acetylated metabolites were 10 to 50 fold higher than that of SDM. 

Renal function impairment No changes were observed in the pharmacokinetics of dipyridamole or its glucuronide metabolite with creatinine clearances ranging from approximately 15 mL/min to more than 100 mL/min if data were corrected for differences in age. Avoid aspirin in patients with severe renal failure (glomerular filtration rate less than 10 mL/min). 

Absorption/Disthbutton - Oral labetalol is completely absorbed peak plasma levels occur in 1 to 2 hours. Steady-state plasma levels during repetitive dosing are reached by about the third day. Due to an extensive first-pass effect, absolute bioavailability is 25%. Protein binding is approximately 50%. Metabolism/Excretion - Metabolism is mainly through conjugation to glucuronide metabolites, which are excreted in urine and in feces (via bile). Elimination half-life is 5.5 to 8 hours. About 55% to 60% of a dose appears in... 

Pharmacokinetics Onset of action occurs within 30 min. Absorption is dependent on body hydration. Metabolized in liver to form glucuronide metabolites. 

Peak blood levels occur within 15 minutes after smoking. The effects last for approximately 4 hours, although it may take more than 24 hours for an individual to return to a normal state. The drugs are stored in fatty tissue and released slowly. PCP has a long half-life ranging from many hours to days, and the PCP glucuronide metabolite can be found in urine for several days or weeks. PCP is found in breast milk. The half-life of ketamine is three to four hours, and metabolites of ketamine are excreted in urine. PCP and ketamine cross the placental barrier, and infants of chronic abusers have been born with cerebral palsy, facial deformities, and behavioral abnormalities. 

It is highly bound to plasma protein (90% to 95%). The major binding protein is ttj-acid glycoprotein. Plasma half life is 3 to 6 hrs, and excreted through urine (95%) breast milk 5% in faeces as glucuronide metabolites. 

Because morphine and its congeners are metabolized primarily in the liver, their use in patients in prehepatic coma may be questioned. Half-life is prolonged in patients with impaired renal function, and morphine and its active glucuronide metabolite may accumulate dosage can often be reduced in such patients. 

Smith MT Neuroexcitatory effects of morphine and hydromorphone Evidence implicating the 3-glucuronide metabolites. Clin Exp Pharmacol Physiol 2000 27 524. [PMID 10874511]... 

Peak plasma concentration of meclofenamate occur 0.5 to 1 h after oral administration. The binding to plasma proteins is over 99% and the plasma elimination half-life is about 2 to 4 h. Meclofenamate is metabolized by oxidation, hydroxylation, dehalogenation, and glucuronidation. Metabolites are excreted mainly in the urine with about 20 to 30% being excreted in the faeces (Koup et al., 1990). A 3-hydroxymethyl metabolite of meclofenamate has been reported to be active. 

Yue, Q.Y., Aim, C., Svensson, J.O., Sawe, J. Quantification of the O- and N-demethylated and the glucuronidated metabolites of codeine relative to the debrisoquine metabolic ratio in urine in ultrarapid, rapid, and poor debrisoquine hydroxylators, Ther. Drug Monit. 1997, 19, 539-542. 

Stuart-Harris, R., S.P. Joel, P. McDonald, D. Currow, et al., The pharmacokinetics of morphine and morphine glucuronide metabolites after subcutaneous bolus injection and subcutaneous infusion of morphine, Br. J. Clin. Pharmacol., 49(3), 207-214, 2000. 

Figure 3.19. Comparison of S/N for glucuronide metabolite of testosterone detected using different IDA survey scans.

The acyl migration of the glucuronide metabolite of the model drug 6,11-dihydro- 11 -oxodibenz (b,e) oxepin-2-acetic acid has also been investigated in urine and pH 7.4 buffer using directly coupled 600 and 750 MHz stop-flow HPLC H NMR spectroscopy [53,54],... 

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