Abstract
The bioavailability of phenytoin, a drug subject to capacity-limited disposition, was examined using linear and nonlinear pharmacokinetic techniques. The linear method (comparative areas) underestimates the essentially complete bioavailability of this drug from capsules (Epanutin, Parke-Davis). The error incurred in using area ratios is inversely related to the rate of absorption of the drug. The time course of absorption of phenytoin capsules is irregular and prolonged over nearly 2 days.
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Supported by Grant 20852 from the National Institutes of General Medical Sciences, NIH.
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Jusko, W.J., Koup, J.R. & Alván, G. Nonlinear assessment of phenytoin bioavailability. Journal of Pharmacokinetics and Biopharmaceutics 4, 327–336 (1976). https://doi.org/10.1007/BF01063122
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DOI: https://doi.org/10.1007/BF01063122