Bioavailability of phenytoin
WebPhenytoin (PHT), sold under the brand name Dilantin among others, is an anti-seizure medication. It is useful for the prevention of tonic-clonic seizures (also known as grand mal seizures) and focal seizures, but not absence seizures. The intravenous form, fosphenytoin, is used for status epilepticus that does not improve with benzodiazepines. It may also be … WebPhenytoin is classified as an antiarrhythmic and can cause SA and AV nodal blocks as well as dysrhythmias due to its effect on voltage-gated sodium channels. 3 Further, since phenytoin is poorly soluble, the parenteral form is administered with propylene glycol, which is a cardiac depressant. 3 The infusion rate of parenteral phenytoin should ...
Bioavailability of phenytoin
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WebA.L. Inselman, D.K. Hansen, in Encyclopedia of Toxicology (Third Edition), 2014 Toxicokinetics. Phenytoin is slowly but nearly completely absorbed in the small intestine; oral bioavailability ranges from 70 to 100%. The drug is widely distributed in the body and is almost completely protein-bound, primarily to albumin. Phenytoin is metabolized … WebPhenytoin Dosing Calculator. This initial program provides some general dosage guidelines based on population averages for the Michaelis-Menten parameters (Km and Vmax). The recommendations do not take into account the following: (1) existence of interacting drugs (3) inter-patient variability (3) existing disease states which may significantly ...
WebApr 1, 1994 · Phenytoin: Phenytoin exhibits marked saturation of metabolism at concentrations in the therapeutic range (10-20 mg/L) (Fig. 2). Consequently, small increases in dose result in large increases in total and unbound steady state drug concentration. ... Saturation of first pass metabolism causing an increase in bioavailability After oral ... WebImpaired Hepatic blood flow leading to an increase in bioavailability caused by a reduction in first pass metabolism (e.g Bioavailabilities of Morphine and Labetalol have been reported to double in patients with Cirrhosis) Decreased protein binding and increased toxicity of drugs highly bound to plasma protein (e.g. Phenytoin, Warfarin) due to ...
WebThe absolute bioavailability of an oral dosage form (Dilantin Kapseals) varied from 57.7 to 85.6% when based on the relationship between the corresponding single dose areas under the curve (AUCs). ... (71.8 to 106.3). Since the variation in the bioavailability and elimination of phenytoin does not allow accurate prediction of the steady-state ... WebApr 14, 2024 · A similar effect resulted in an absolute bioavailability in rats and dogs of 5%. After a single dose of 25 mg, maximum plasma levels of 18 ng/ml are reached after 2 hours. Concomitant intake with food increases the bioavailability by 40%. Distribution: The volume of distribution of exemestane, not corrected for the oral bioavailability, is ca ...
WebBIOAVAILABILITY According to a biopharmaceutic expert, the term bioavailability may be defined as the rate and extent to which the ingredient is absorbed from the drug product into the body or to the site of action. ... the intoxication was caused by altering one of the excipients from calcium phosphate to lactose in the drug product Phenytoin ...
WebTo determine inter-lot and intra-subject variability in the bioavailability of the 100 mg extended phenytoin sodium capsules. In addition, to determine the effect of gender and menstrual cycle on phenytoin bioavailability. Methods. Three different lots of extended phenytoin sodium capsules were given to 12 healthy male and 12 healthy female ... ontario ltd trackingWebThe bioavailability of seven phenytoin (DPH) formulations, five brands of tablets and two suspensions, was measured in a cross-over study with six healthy volunteers. Single doses of 600 mg of DPH were used and the bioavailability was determined as the area under the serum DPH concentration-time curve (AUC). ione utecht obituaryWebMar 24, 1993 · The bioavailability of the derived phenytoin relative to intravenous phenytoin is approximately 100% following intravenous or intramuscular administration. The half-life for conversion of ... ontario low income tax credit 2023WebThe bioavailability of seven phenytoin (DPH) formulations, five brands of tablets and two suspensions, was measured in a cross-over study with six healthy volunteers. Single doses of 600 mg of DPH were used and the bioavailability was determined as the area under the serum DPH concentration-time curve (AUC). Highly significant differences ... ontario lowriders i usa california youtubeWebJan 1, 2013 · Using a crossover design, phenytoin was administered (8.8 mg/kg of body weight, IV and PO) to 6 horses to determine bioavailability (F). Phenytoin also was administered orally twice daily for 5 ... ontario lumpers websiteWebsystem (SEDDS) of phenytoin, and to compare its relative bioavailability to a commercially available suspension. Results showed that, Phenytoin was successfully formulated as a stable S S formulation that showed significantly improved in vitro release of phenytoin when compared to a commercially available phenytoin suspension. ontario ltc wait timesWebJun 19, 2014 · This variation in bioavailability becomes a greater issue when a switch from one generic manufacturer to another is attempted because of the lack of bioequivalence studies between different generic formulations. ... Phenytoin: Generic interchange of phenytoin is complicated not only by its NTI but also by its nonlinear kinetics. ontario ltc homes act