Pharmacogenetics and enzyme induction/inhibition properties of antiepileptic drugs.
ABSTRACT One of the major differences between the older antiepileptic drugs (AEDs) and the newer AEDs is the potential of the older AEDs for significant interactions with other medications. Many of the drug-drug interactions involving the older AEDs are reciprocal, i.e., both drugs affect each other. In contrast, the newer AEDs have either no or limited drug interaction potential. Despite our extensive understanding of and our ability to predict drug-drug interactions, serious drug interactions still occur. More than 30% of all new seizures occur in the elderly, and because this population may be taking a variety of other medications the addition of an AED can have profound impact on these other therapies. In women, the use of enzyme-inducing AEDs can cause significant alterations of sex hormones and can decrease the efficacy of oral contraceptives. In children and adults, the use of enzyme inducers may result in long-term endocrine effects, including bone loss and lipid, thyroid, and sex hormone abnormalities. Phenytoin and phenobarbital are metabolized by cytochrome P450 isozymes, with activity dependent on genetic polymorphism (CYP2C9, CYP2C19). The dosing of the newer AEDs is not affected by genetic polymorphism. The decreased induction and inhibition effects and the lack of significant genetic polymorphism of the newer AEDs allow increased ease of use and perhaps greater safety, especially for patients taking multiple medications.
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ABSTRACT: Various dietary components, biological supplements might influence the incidence or management of epilepsy. Some studies reported that the supplementation with individual nutrients reduced seizure occurrence or improved other facets of health in epileptic patients. The beneficial dietary involvement identifying and avoiding allergenic foods, and avoiding suspected causing agents such as alcohol, aspartame, and monosodium glutamate. The Atkins diet (very low in carbohydrates) is a less preventive type diet that may be effective in some cases. Nutrients that may lessen seizure occurrence include vitamin B6, magnesium, vitamin E, manganese, taurine, dimethylglycine, and omega-3 fatty acids. Use of thiamine or vitamin B1 may improve cognitive function in epileptic patients. Supplementation with folic acid, vitamin B6, biotin or viatamine H, vitamin D, and L-carnitine may be needed to prevent or treat deficiencies resulting from the use of antiepileptic drugs. Vitamin K1 is recommended near the end of pregnancy for women taking antiepileptic drugs. Melatonin may reduce seizure occurrence in some cases, and progesterone may be useful for women with cyclic exacerbations of seizures. In the majority of cases, nutritional therapy is not a substitute for antiepileptic drugs. In some cases, depending on the effectiveness of the involvement, dosage reduction or discontinuation of drugs may be possible. However, nutrient supplementation may be necessary to prevent or reverse the effects of certain deficiencies that regularly result from the use of antiepileptic drugs.Current Science Perspectives. 01/2015; 1(1):1-11.
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ABSTRACT: The induction and inhibition of cytochrome P450 isoenzymes by antiepileptic drugs lead to changes in the clearance of anesthetic drugs eliminated via hepatic metabolism. We investigated the duration of the sedation and additional anesthetic needs during magnetic resonance imaging in epileptic children receiving antiepileptic drugs that cause either enzyme induction or inhibition.Brazilian journal of anesthesiology (Elsevier). 09/2014; 64(5):320-325.
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ABSTRACT: The induction and inhibition of cytochrome P450 isoenzymes by antiepileptic drugs lead to changes in the clearance of anesthetic drugs eliminated via hepatic metabolism. We investigated the duration of the sedation and additional anesthetic needs during magnetic resonance imaging in epileptic children receiving antiepileptic drugs that cause either enzyme induction or inhibition.Revista Brasileira de Anestesiologia 09/2014; 64(5):320-5. · 0.42 Impact Factor