DiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPhenomena and ProcessesHealth Care
PhenytoinAnticonvulsantsHalf-LifePrimidoneArea Under CurveCarbamazepineDrug InteractionsMetabolic Clearance RateBiological AvailabilityAdministration, OralPharmacokineticsEpilepsyInjections, IntravenousPhenobarbitalValproic AcidChromatography, High Pressure LiquidDose-Response Relationship, DrugInfusions, IntravenousTissue DistributionCross-Over StudiesSeizuresEthosuximideTriazinesDrug Administration ScheduleFood-Drug InteractionsBiotransformationEpilepsy, Post-TraumaticFluorescence Polarization ImmunoassayPhenylethylmalonamideProdrugsEpilepsy, Tonic-ClonicCytochrome P-450 CYP3AHydantoinsDrug Dosage CalculationsAryl Hydrocarbon HydroxylasesBlood ProteinsStatus EpilepticusDrug MonitoringKinetics
CarbamazepineExtended phenytoin sodiumAbsorptionPharmacodynamicsDoseSodiumConcentrationsFosphenytoinForm of phenytoinMichaelis MentenUnboundMetabolismConcentrationDosageEpilepsyClinicalHepaticBioavailabilityBiopharmaceuticsDosesRenalOccur during prDrugsSeizuresToxicitySteady stateClonazepamMedicationsAcidPatientsAdministrationIncreaseAdultParametersLevelsLinearEffectsEffectClearance
Carbamazepine7
Extended phenytoin sodium1
  • DILANTIN is available as 30 mg and 100 mg extended phenytoin sodium capsules. (nih.gov)
Absorption3
  • Phenytoin is a weak acid and has erratic GI absorption. (medscape.com)
  • All factors must be considered: addition of interacting drugs, changes in absorption (eg enteral feeding + oral administration of phenytoin), concomitant disease state(s) which may alter phenytoin kinetics, etc. (globalrph.com)
  • Early in his career, he identified the interference of phenytoin oral absorption by the concurrent use of enteral feeding and investigated the influences of obesity on aminoglycoside, vancomycin, and theophylline dosing. (washington.edu)
Pharmacodynamics2
  • Pharmacokinetics is the study of how an organism affects a drug, whereas pharmacodynamics (PD) is the study of how the drug affects the organism. (wikipedia.org)
  • Since 1988, Larry has been the author of the Clinical Pharmacokinetics and Pharmacodynamics chapter in Pharmacotherapy (aka DiPiro), the gold standard textbook for pharmacy curricula all over the world, for 11 editions. (washington.edu)
Dose7
  • Phenytoin metabolism is dose dependent. (medscape.com)
  • Purpose: We performed a population pharmacokinetic analysis of phenytoin after intravenous administration of fosphenytoin sodium in healthy, neurosurgical, and epileptic subjects, including pediatric patients, and determined the optimal dose and infusion rate for achieving the therapeutic range. (elsevierpure.com)
  • In adult patients, the optimal dose and infusion rate of phenytoin for achieving the therapeutic range was 22.5 mg/kg and 3 mg/kg/min respectively. (elsevierpure.com)
  • However, many pediatric patients showed phenytoin concentration within the toxic range after administration of a dose of 30 mg/kg. (elsevierpure.com)
  • Clonazepam pharmacokinetics are dose-independent throughout the dosing range. (nih.gov)
  • Phenytoin: moderate, obtain a single dose pharmacokinetics of health professionals. (amanovaraonlus.it)
  • BUSULFEX pharmacokinetics showed consistency between dose 9 and dose 13 as demonstrated by reproducibility of steady state Cmax and a low coefficient of variation for this parameter. (clustermed.info)
Sodium7
  • Phenytoin blocks voltage-sensitive sodium channels in neurons. (medscape.com)
  • Phenytoin Sodium and breastfeeding. (e-lactancia.org)
  • Phenytoin Sodium is also known as Phenytoin . (e-lactancia.org)
  • Conclusions: The pharmacokinetics of phenytoin after intravenous administration of fosphenytoin sodium could be described using a linear two-compartment model. (elsevierpure.com)
  • The administration of fosphenytoin sodium 22.5 mg/kg at an infusion rate of 3 mg/kg/min was optimal for achieving the desired plasma phenytoin concentration. (elsevierpure.com)
  • Efficacy of individualized phenytoin sodium loading doses administered by intravenous infusion. (globalrph.com)
  • DILANTIN extended capsules and parenteral DILANTIN are formulated with the sodium salt of phenytoin. (drugs.com)
Concentrations8
  • Because CNS tissue levels are higher than in serum, levels may underestimate CNS concentrations of phenytoin. (medscape.com)
  • Monitor unbound phenytoin concentrations in these patients. (nih.gov)
  • Estimating phenytoin concentrations by the Sheiner-Tozer method in adults with pronounced hypoalbuminemia. (globalrph.com)
  • Renal function and therapeutic concentrations of phenytoin. (globalrph.com)
  • Therapeutic effect without clinical signs of toxicity occurs more often with serum total concentrations between 10 and 20 mcg/mL (unbound phenytoin concentrations of 1 to 2 mcg/mL), although some mild cases of tonic-clonic (grand mal) epilepsy may be controlled with lower serum levels of phenytoin. (drugs.com)
  • Decreased serum concentrations of phenytoin may occur during pregnancy because of altered phenytoin pharmacokinetics. (drugs.com)
  • Periodic measurement of serum phenytoin concentrations should be performed during pregnancy, and the DILANTIN dosage should be adjusted as necessary. (drugs.com)
  • our observations about the influence of polytherapies on lamotrigine pharmacokinetics confirm the relevance of quantifying this antiepileptic drug plasma concentrations in the process of treatment optimization. (bvs.br)
Fosphenytoin3
  • In addition, fosphenytoin (water-soluble phenytoin prodrug) may be administered intramuscularly. (medscape.com)
  • However, cardiac toxicity was reported even after rapid administration of fosphenytoin that does not contain propylene glycol, suggesting intrinsic phenytoin cardiac toxicity. (medscape.com)
  • Results: We used a linear two-compartment model with conversion of fosphenytoin to phenytoin. (elsevierpure.com)
Form of phenytoin1
  • The free acid form of phenytoin is used in DILANTIN-125 Suspension and DILANTIN Infatabs. (drugs.com)
Michaelis Menten1
  • Michaelis Menten parameters were determined for the conversion of PHT to p-hydroxy phenytoin in seven different microsomal preparations with the addition of 0, 2, and 4% BSA. (aspetjournals.org)
Unbound3
  • Only the free unbound phenytoin has biological activity. (medscape.com)
  • Because the fraction of unbound phenytoin is increased in patients with renal or hepatic disease, or in those with hypoalbuminemia, the monitoring of phenytoin serum levels should be based on the unbound fraction in those patients [see Warnings and Precautions (5.11) and Use in Specific Populations (8.6) ]. (drugs.com)
  • Because of potential changes in protein binding during pregnancy, the monitoring of phenytoin serum levels should be based on the unbound fraction. (drugs.com)
Metabolism3
  • Genetic polymorphism in the cytochrome enzymes that metabolize phenytoin may be responsible for variable rates of metabolism and thus susceptibility to toxicity, even in individuals taking appropriate doses. (medscape.com)
  • The effect of bovine serum albumin (BSA) on human liver metabolism, in vitro , of 14 C-phenytoin (PHT) was studied. (aspetjournals.org)
  • These findings for phenytoin metabolism suggest that the addition of albumin to incubation media for slices or microsome experiments may yield K m estimates that are more representative of in vivo values. (aspetjournals.org)
Concentration5
  • Blood levels of phenytoin reflect only total serum concentration of the drug. (medscape.com)
  • Pharmacokinetics is based on mathematical modeling that places great emphasis on the relationship between drug plasma concentration and the time elapsed since the drug's administration. (wikipedia.org)
  • The therapeutic range for total plasma phenytoin concentration is 10-20 μg/mL. (elsevierpure.com)
  • In pediatric patients, the total plasma concentration of phenytoin was within the therapeutic range for a shorter duration than that in adult patients at 22.5 mg/kg (3 mg/kg/min). (elsevierpure.com)
  • Monotherapy is usual y considered LTG linear pharmacokinetics, its plasma concentration as the initial strategy, and despite 47% of patients having values show high inter-individual variability, as commonly their seizures under control with only one antiepileptic seen in clinical practice. (bvsalud.org)
Dosage2
  • Phenytoin dosage individualization--five methods compared in the elderly. (globalrph.com)
  • With recommended dosages, a period of seven to ten days may be required to achieve phenytoin steady-state blood levels, and changes in dosage (increase or decrease) should not be carried out at intervals shorter than seven to ten days. (drugs.com)
Epilepsy1
Clinical7
Hepatic1
Bioavailability1
Biopharmaceutics1
Doses1
  • Higher doses of aspirin may increase phenytoin levels and toxicity during long-term use of both drugs. (epnet.com)
Renal1
  • Controlled studies examining the influence of gender and age on clonazepam pharmacokinetics have not been conducted, nor have the effects of renal or liver disease on clonazepam pharmacokinetics been studied. (nih.gov)
Occur during pr1
Drugs4
  • IUPAC definition Pharmacokinetics: Process of the uptake of drugs by the body, the biotransformation they undergo, the distribution of the drugs and their metabolites in the tissues, and the elimination of the drugs and their metabolites from the body over a period of time. (wikipedia.org)
  • Drugs similar to phenytoin are ethotoin (Peganone) and mephenytoin (Mesantoin). (epnet.com)
  • Pharmacokinetics is a quantitative study of the drug movement, and it includes the response of the body to drugs. (missionnursing.in)
  • Phenytoin and warfarin are examples of highly protein-bound drugs with a higher risk of toxic effects when the serum albumin level decreases. (msdmanuals.com)
Seizures1
  • Signs and symptoms of phenytoin toxicity typically correspond to the serum level, and progress from occasional mild nystagmus at 10-20 mcg/mL (the therapeutic range) to coma and seizures at levels above 50 mcg/mL (see Presentation and Workup ). (medscape.com)
Toxicity2
  • Historically, phenytoin was used as an antidysrhythmic agent, especially in the treatment of dysrhythmias due to digoxin toxicity. (medscape.com)
  • Orally administered phenytoin is rarely, if ever, associated with cardiac toxicity. (medscape.com)
Steady state1
  • In pharmacokinetics, steady state refers to the situation where the overall intake of a drug is fairly in dynamic equilibrium with its elimination. (wikipedia.org)
Clonazepam1
Medications2
  • Certain medications can interfere with phenytoin levels. (medscape.com)
  • 1-5 It has also been suggested that ginkgo might interfere with the effectiveness of some anti-seizure medications, including phenytoin. (epnet.com)
Acid1
  • salicylates, phenytoin  Increase serum acid glycoprotein  Basic drug such as lidocaine displays increased protein binding. (edocr.com)
Patients4
  • 2. Bachmann KA, Belloto RJ Jr. Differential kinetics of phenytoin in elderly patients. (globalrph.com)
  • Related ArticlesComparison of eight phenytoin dosing methods in institutionalized patients. (globalrph.com)
  • Pharmacokinetics The pharmacokinetics of BUSULFEX were studied in 59 patients participating in a prospective trial of a BUSULFEX-cyclophosphamide preparatory regimen prior to allogeneic hematopoietic progenitor stem cell transplantation. (clustermed.info)
  • The Many Faces also needed to not intended to is an injectable stress that legal, veterinary, buy viagra online safely Patients taking Accutane advised of the avoid phenytoin intoxication, blood against the or withdrawal symptoms be made5, 6. (fmvoley.com)
Administration1
  • Phenytoin administration has been associated with toxic effects. (medscape.com)
Increase1
  • Prenatal exposure to phenytoin may increase the risks for congenital malformations and other adverse developmental outcomes. (nih.gov)
Adult1
Parameters1
  • Pharmacokinetic parameters of phenytoin, such as total clearance and central and peripheral volume of distribution were influenced by body weight. (elsevierpure.com)
Levels1
Linear2
  • Commentary to "linear and nonlinear system approaches in pharmacokinetics. (umn.edu)
  • Linear and nonlinear system approaches in pharmacokinetics: How much do they have to offer? (umn.edu)
Effects1
  • 8 This raises the concern that white willow might have similar effects on phenytoin, though this has not been proven. (epnet.com)
Effect1
  • Because phenytoin is principally bound to albumin, we also explored the effect of albumin on the V max and K m values obtained, in vitro . (aspetjournals.org)
Clearance1