Klin Farmakol Farm. 2021;35(3):78-79

Drug interactions of antiepileptic drugs. Part 3: interaction with hormonal contraception

Blanka Kořístková^{1, 2}, Milan Grundmann¹

¹ Ústav klinické farmakologie, Lékařská fakulta, Ostravská Univerzita, Ostrava

² Oddělení klinické farmakologie, Ústav laboratorní medicíny, Fakultní nemocnice Ostrava

The metabolism of contraceptives is enhanced and thereby contraceptive failure might occur in combination with carbamazepine, eslicarbazepine, felbamate, phenobarbital, phenytoin, oxcarbazepine, perampanel, primidone, rufinamide or higher levels of topiramate. Estrogen component considerably declines lamotrigine level with the necessity to increase the dose. Lamotrigine concentrations consequently significantly increase during the hormonal contraceptive washout week and may be associated with intermittent lamotrigine-related toxicity. Lamotrigine produces a modest reduction in the progesterone level which might result in contraceptive failure in patients using the progesterone-only pill. The metabolism of hormonal contraceptives is no affected with: clonazepam, ethosuximide, gabapentin, lacosamide, levetiracetam, pregabalin, retigabine, tiagabine, vigabatrin, valproic acid, zonisamid. The effect has not been evaluated in clobazam. A pharmacokinetic interaction would not be anticipated. It is not known whether stiripentol or sulthiame affect hormonal contraception, but they can increase plasma level of hormonal contraceptives and thus necessitate lower doses to be prescribed.

Keywords: drug‑drug ineractions, antiepileptics, concentration, hormonal contraception, hormone replacement therapy.

Published: November 8, 2021  Show citation