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. Kempster and J. Frankel and M. Bovingdon and R. Webster and A. Lees and G. 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… Expand
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It is concluded that progression of the underlying pathology of the disease is probably responsible for loss of benefit in patients on chronic levodopa therapy and discovery of the exact causes may provide a rational basis for new therapy. Expand
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Publisher Summary This chapter discusses that Parkinson's disease, although in most respects a chronic, progressive disorder, can also be seen as a paroxysmal condition. Sudden, extreme, andExpand
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Asymmetry of substantia nigra neuronal loss in Parkinson's disease and its relevance to the mechanism of motor fluctuations
  • J Neurol Neurosurg Psychiatry
  • 1989
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