Current drug metabolism
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Current drug metabolism · Jul 2012
ReviewGrowing up with midazolam in the neonatal and pediatric intensive care.
A variety of developmental changes is of influence on the pharmacokinetics and pharmacodynamics of midazolam in neonatal and pediatric intensive care patients. However, dosing regimens in children are based upon rather empirical extrapolations from the dosing regimens in adults. Based on current available studies it appears that with the rising of age, the pharmacokinetics of intravenously administered midazolam alter, resulting in a shorter half-life due to a higher hepatic clearance in older children as compared to newborn. ⋯ In conclusion, there is a large interindividual variability in the response to midazolam in children, which may be caused by differences in pharmacokinetics and pharmacodynamics. Both are subject to considerable developmental changes. It remains remarkable that high-quality evidence to support the use of midazolam for continuous sedation in the neonatal and pediatric intensive care setting is lacking.
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Current drug metabolism · Jun 2012
ReviewHerb-drug interactions and mechanistic and clinical considerations.
Herbal medicines are often used in combination with conventional drugs, and this may give rise to the potential of harmful herb-drug interactions. This paper updates our knowledge on clinical herb-drug interactions with an emphasis of the mechanistic and clinical consideration. In silico, in vitro, animal and human studies are often used to predict and/or identify drug interactions with herbal remedies. ⋯ The underlying mechanisms for most reported herb-drug interactions are not fully understood, and pharmacokinetic and/or pharmacodynamic mechanisms are implicated in many of these interactions. In particular, enzyme induction and inhibition may play an important role in the occurrence of some herbdrug interactions. Because herb-drug interactions can significantly affect circulating levels of drug and, hence, alter the clinical outcome, the identification of herb-drug interactions has important implications.
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Current drug metabolism · Nov 2010
ReviewMetabolism of benzodiazepine and non-benzodiazepine anxiolytic-hypnotic drugs: an analytical point of view.
A review with 132 references. Several kinds of anxiolytic and hypnotic drugs are currently available on the market. Although BZDs are surely the most frequently prescribed among them, several chemically unrelated compounds have been commercialised, which can provide similar or even higher efficacy and tolerability. ⋯ The most important studies on the metabolic characteristics of several non-benzodiazepine anxiolytics and hypnotics are reported and briefly discussed in this review; moreover, the analytical methods related to these studies are also described and commented upon and their characteristics are highlighted. Finally, an update is included on recent (2007-2010) metabolism and pharmacokinetic studies on benzodiazepines. A monograph is included for each of the following drugs: zolpidem, zaleplon, zopiclone, ramelteon, buspirone and tandospirone; updates are included for the following benzodiazepines: alprazolam, bromazepam, diazepam, flunitrazepam, lorazepam, midazolam, oxazepam and triazolam.
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Current drug metabolism · Jul 2010
ReviewDihydrocodeine as an opioid analgesic for the treatment of moderate to severe chronic pain.
Dihydrocodeine (DHC) is a semi-synthetic analogue of codeine which was formed by the hydrogenation of the double tie in the main chain of the codeine molecule. DHC is used as an analgesic, antitussive and antidiarrhoeal agent; it is also used for the treatment of opioid addiction. Limited data is available on the relative potency of DHC to other opioids. ⋯ DHC possesses approximately 1/6(th) of the morphine analgesic effect when drugs are administered orally. In this article pharmacokinetics, pharmacodynamics, dosing guidelines, adverse effects and clinical studies of DHC in pain management are shown with focus on cancer pain. The impact of CYP2D6 activity on DHC analgesia was discussed and a proposal of calculation equianalgesic doses of DHC to other opioids was put forward.
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Current drug metabolism · Oct 2008
ReviewClinical pharmacogenetics and potential application in personalized medicine.
The current 'fixed-dosage strategy' approach to medicine, means there is much inter-individual variation in drug response. Pharmacogenetics is the study of how inter-individual variations in the DNA sequence of specific genes affect drug responses. This article will highlight current pharmacogenetic knowledge on important drug metabolizing enzymes, drug transporters and drug targets to understand interindividual variability in drug clearance and responses in clinical practice and potential use in personalized medicine. ⋯ Drugs with a narrow therapeutic index are thought to benefit more from pharmacogenetic studies. For example, warfarin serves as a good practical example of how pharmacogenetics can be utilized prior to commencement of therapy in order to achieve maximum efficacy and minimum toxicity. As such, pharmacogenetics has the potential to achieve optimal quality use of medicines, and to improve the efficacy and safety of both prospective and licensed drugs.