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Topiramate: Pharmacokinetics and Pharmacodynamics

Published online by Cambridge University Press:  18 September 2015

J.H. Schneiderman*
Affiliation:
Departments of Medicine and Physiology, University of Toronto, Toronto
*
Rm 116 E.K. Jones Building, Wellesley Hospital, 160 Wellesley Street E., Toronto, Ontario, Canada M4Y 1J3
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Abstract:

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Topiramate is a structurally novel anti-epileptic drug with at least 3 postulated mechanisms of action including: 1) potentiation of GABA responses, 2) impairment of AMPA/kainate glutamate receptors and 3) suppression of high frequency action potential firing. It has a favourable pharmacokinetic profile with rapid absorption, good bio-availability, linear pharmacokinetics, relatively long half-life and limited pharmacokinetic drug interactions. However, topiramate can reduce the estrogen component of oral contraceptive medications. Women may require birth control preparations containing 50 (Xg of estrogen. Topiramate clearance is reduced in severe renal failure and increased by enzyme-inducing antiepileptic drugs. The dose of topiramate may have to be reduced in renal failure or when withdrawing enzyme inducers.

Type
Research Article
Copyright
Copyright © Canadian Neurological Sciences Federation 1998

References

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