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PubMed · 3734138

Pharmacokinetics: dose-dependent changes.

T R Browne·D J Greenblatt·J E Evans·G K Szabo·B A Evans·G E Schumacher
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Abstract

Stable-isotope tracer methods are described for answering the following questions about a drug: Does the drug exhibit dose-dependent changes in pharmacokinetic properties? What are the drug's Michaelis constant (Km) and maximum velocity (Vmax) for enzymatic biotransformation; Are the dose-dependent pharmacokinetic changes great enough to be clinically important? and Which routes of the drug's biotransformation are responsible for the drug's dose-dependent pharmacokinetic properties? Illustrative data are provided from tracer studies performed with a drug with dose-dependent pharmacokinetic properties, phenytoin, and a drug that does not exhibit dose-dependent pharmacokinetic properties, phenobarbital. The advantages and disadvantages of the described stable-isotope methods are discussed.

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BiotransformationDose-Response Relationship, DrugHalf-LifeHumansKineticsPharmaceutical PreparationsPhenobarbitalPhenytoinTime FactorsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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T R Browne, D J Greenblatt, J E Evans, G K Szabo, B A Evans, G E Schumacher. Pharmacokinetics: dose-dependent changes.. https://doi.org/10.1002/j.1552-4604.1986.tb03559.x

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