Levodopa peripheral pharmacokinetics and duration of motor response in Parkinson's disease.

@article{Kempster1989LevodopaPP,
  title={Levodopa peripheral pharmacokinetics and duration of motor response in Parkinson's disease.},
  author={P. A. Kempster and J. P. Frankel and M. Bovingdon and Roy A. Webster and Andrew John Lees and Gerald M. Stern},
  journal={Journal of Neurology, Neurosurgery \& Psychiatry},
  year={1989},
  volume={52},
  pages={718 - 723}
}
To assess the relative influence of central pharmacodynamic and peripheral pharmacokinetic factors on the duration of motor response to levodopa, the relationship between motor function and plasma levodopa levels was studied in 31 Parkinsonian patients. Duration of benefit from single levodopa doses while fasting depended on the degree to which the plasma levodopa level had declined over four hours; wearing off occurred when the plasma levodopa level had fallen to approximately 50% of peak… 

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...

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