toiron chelators(deferasirox). Monitor serum ferritin and
adjust dose.oTheoretical
▶Isoniazidincreases the concentration ofantiepileptics
(fosphenytoin, phenytoin).oStudy→Also seeTABLE 12
p. 850
▶Isoniazidmarkedly increases the concentration of
carbamazepineandcarbamazepineincreases the risk of
hepatotoxicity when given withisoniazid. Monitor
concentration and adjust dose.rStudy→Also seeTABLE 1
p. 847
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
toivabradine. Adjust dose.oTheoretical
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to moderately to markedly
decrease the exposure toivacaftor. Avoid.rStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
toixazomib. Avoid.rStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tolapatinib. Avoid.rStudy
▶Carbamazepineis predicted to decrease the exposure to
ledipasvir. Avoid.rTheoretical
▶Antiepileptics(fosphenytoin, phenytoin)decrease the effects of
levodopa.oStudy
▶Antiepileptics(carbamazepine, eslicarbazepine, fosphenytoin,
oxcarbazepine, perampanel, phenobarbital, phenytoin,
primidone, rufinamide, topiramate)are predicted to decrease
the efficacy oflevonorgestrel. For FSRH guidance, see
Contraceptives, interactionsp. 497.rTheoretical
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tolinagliptin.oStudy
▶Antiepileptics(carbamazepine, oxcarbazepine)are predicted to
increase the risk of neurotoxicity when given withlithium.
rAnecdotal
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tolomitapide. Monitor and adjust dose.oTheoretical→
Also seeTABLE 1p. 847
▶Antiepileptics(fosphenytoin, phenytoin)decrease the effects of
loop diuretics(furosemide).oStudy
▶Lumacaftoris predicted to decrease the exposure to
antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone). Avoid.rTheoretical
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tolurasidone. Avoid.oStudy→Also seeTABLE 11p. 849
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tomacitentan. Avoid.rStudy
▶Macrolides(clarithromycin)slightly increase the concentration
ofcarbamazepine. Monitor concentration and adjust dose.
rStudy
▶Macrolides(clarithromycin)are predicted to very slightly
increase the exposure toperampanel.nStudy
▶Macrolides(erythromycin)markedly increase the concentration
ofcarbamazepine. Monitor concentration and adjust dose.
rStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tomaraviroc. Adjust dose.rStudy
▶Phenytoinis predicted to decrease the exposure tomelatonin.
oTheoretical
▶Levetiracetamdecreases the clearance ofmethotrexate.r
Anecdotal
▶Antiepileptics(phenobarbital, primidone)are predicted to
decrease the exposure tometronidazole.oStudy
▶Antiepileptics(fosphenytoin, phenobarbital, phenytoin,
primidone)are predicted to decrease the effects of
metyrapone. Avoid.oStudy
▶Antiepileptics(phenobarbital, primidone)are predicted to
decrease the exposure tomianserin.oStudy→Also see
TABLE 11p. 849
▶Carbamazepinemarkedly decreases the exposure tomianserin.
Adjust dose.oStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tomidazolam. Monitor and adjust dose.oStudy→Also
seeTABLE 11p. 849
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tomidostaurin. Avoid.rStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tomirtazapine. Adjust dose.oStudy→Also seeTABLE 11
p. 849
▶Mitotaneis predicted to decrease the exposure toperampanel.
Monitor and adjust dose.oStudy
▶Antiepileptics(carbamazepine, phenobarbital, primidone)are
predicted to decrease the exposure tomodafinil.n
Theoretical
▶Antiepileptics(fosphenytoin, phenytoin)are predicted to
decrease the exposure tomodafinilandmodafinilis predicted
to increase the concentration ofantiepileptics(fosphenytoin,
phenytoin). Monitor concentration and adjust dose.o
Theoretical
▶Antiepileptics(phenobarbital, primidone)are predicted to
increase the effects ofmonoamine-oxidase A and B inhibitors,
irreversible.rTheoretical
▶Carbamazepineis predicted to increase the risk of severe toxic
reaction when given withmonoamine-oxidase A and B
inhibitors, irreversible. Avoid and for 14 days after stopping
the MAOI.rTheoretical
▶Carbamazepineis predicted to decrease the effects of
monoclonal antibodies(brentuximab vedotin).rTheoretical
▶Monoclonal antibodies(tocilizumab)are predicted to decrease
the exposure toantiepileptics(fosphenytoin, phenytoin).
Monitor and adjust dose.oTheoretical
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tomontelukast.nStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to markedly decrease the
exposure tonaloxegol. Avoid.oStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to slightly decrease the
exposure tonateglinide.nStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tonetupitant. Avoid.rStudy
▶Carbamazepineis predicted to decrease the effects of (but
acute use increases the effects of)neuromuscular blocking drugs,
non-depolarising(atracurium, cisatracurium, pancuronium,
rocuronium, vecuronium). Monitor and adjust dose.o
Study
▶Antiepileptics(fosphenytoin, phenytoin)decrease the effects of
(but acute use increases the effects of)neuromuscular blocking
drugs, non-depolarising(atracurium, cisatracurium,
pancuronium, rocuronium, vecuronium).oStudy
▶Nevirapineis predicted to decrease the concentration of
antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)andantiepileptics(carbamazepine,
fosphenytoin, phenobarbital, phenytoin, primidone)are
predicted to decrease the concentration ofnevirapine.r
Study
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to moderately decrease
the exposure tonilotinib. Avoid.rStudy
▶Carbamazepineis predicted to decrease the exposure to
nintedanib.oStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
tonitisinone. Adjust dose.oTheoretical
▶Antiepileptics(carbamazepine, eslicarbazepine, fosphenytoin,
oxcarbazepine, perampanel, phenobarbital, phenytoin,
primidone, rufinamide, topiramate)are predicted to decrease
the efficacy ofnorethisterone. For FSRH guidance, see
Contraceptives, interactionsp. 497.rAnecdotalBNFC 2018 – 2019 Antiepileptics—Antiepileptics 867
Interactions|Appendix 1A1