Clinical pharmacology and therapeutics
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Clin. Pharmacol. Ther. · Nov 2001
Randomized Controlled Trial Clinical TrialEffect of high-dose lansoprazole on intragastic pH in subjects who are homozygous extensive metabolizers of cytochrome P4502C19.
Lansoprazole is mainly metabolized by cytochrome P4502C19 (CYP2C19) in the liver. The effect of lansoprazole is assumed to be insufficient in subjects who are homozygous extensive metabolizers of CYP2C19. This study aimed to examine whether the CYP2C19 genotype status affected the acid-inhibitory effects of lansoprazole and to develop a strategy to overcome this pharmacogenetic problem. ⋯ The effect of lansoprazole on intragastric pH depended significantly on CYP2C19 genotype status. Complete acid inhibition could be achieved by the frequent administration of lansoprazole (eg, 30 mg 4 times daily) in subjects who were homozygous extensive metabolizers. A genotyping test of CYP2C19 status appears useful for prescribing an optimal dosing scheme of lansoprazole.
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Clin. Pharmacol. Ther. · Nov 2001
Stereoselective pharmacokinetics of ketamine: R(-)-ketamine inhibits the elimination of S(+)-ketamine.
We investigated the pharmacokinetics of ketamine with special regard to enantiomer-specific differences. ⋯ These results demonstrate that R(-)-ketamine inhibits the elimination of S(+)-ketamine.
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Clin. Pharmacol. Ther. · Oct 2001
Comparative Study Clinical TrialIbuprofen pharmacokinetics in preterm infants with patent ductus arteriosus.
Our objective was to study the pharmacokinetics of ibuprofen in premature infants with patent ductus arteriosus on day 3 and day 5 after birth. ⋯ Ibuprofen pharmacokinetics showed a large interindividual variation in premature infants during treatment for patent ductus arteriosus, and significant changes may occur between day 3 and day 5 after birth in those infants with a closing ductus. These findings may have implications for the treatment schedule with ibuprofen in patients with patent ductus arteriosus.
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Clin. Pharmacol. Ther. · Sep 2001
Randomized Controlled Trial Comparative Study Clinical TrialGender and the placebo analgesic effect in acute pain.
Our objective was to examine the placebo arms from a series of clinical trials in which the post-third molar extraction dental pain model was used to elucidate the time course of the placebo effect and the proportion of the population that are responders, as well as to evaluate whether the placebo analgesic response of female subjects may differ from that of male subjects. ⋯ The results demonstrated no gender difference in response to placebo. These results were obtained from the post-third molar extraction situation, in which the least possible confounding factors were present. To fully establish the generality of this phenomenon, studies should be carried out in other pain models.
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Clin. Pharmacol. Ther. · Jul 2001
Analgesic efficacy of rectal versus oral acetaminophen in children after major craniofacial surgery.
Analgesic acetaminophen (INN, paracetamol) plasma concentrations after major surgery in neonates and infants have not yet been established in the literature. We therefore conducted a study in our intensive care unit. ⋯ These are the first data showing that the analgesic acetaminophen plasma concentration after major surgery in this age group does not always reach the 10 to 20 mg/L level. These data also show that, after a rectal loading dose of 40 mg/kg has been given during surgery, the best way of administering acetaminophen after craniofacial surgery is the rectal route.