Plasma and salivary pharmacokinetics of caffeine in man

@article{Newton2004PlasmaAS,
  title={Plasma and salivary pharmacokinetics of caffeine in man},
  author={Ronald Newton and L. J. Broughton and Margareta Lind and P. J. Morrison and Howard J. Rogers and I. D. Bradbrook},
  journal={European Journal of Clinical Pharmacology},
  year={2004},
  volume={21},
  pages={45-52}
}
SummaryPlasma and salivary caffeine concentrations were measured by gas-liquid chromatography in 6 healthy caffeine-free volunteers following oral administration of 50, 300, 500 and 750 mg caffeine. Caffeine was also given to a single subject intravenously in doses of 300, 500 and 750 mg. Caffeine was rapidly absorbed and was completely available at all doses. The apparent first-order elimination rate constant decreased linearly with dose and was 0.163±0.081 h−1 for 50 mg and 0.098±0.027 h−1… 
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