▶Isoniazidis predicted to increase the risk of peripheral
neuropathy when given withdidanosine.rTheoretical→
Also seeTABLE 1p. 847→Also seeTABLE 12p. 850
▶Isoniazidincreases the risk of optic neuropathy when given
withethambutol.rAnecdotal
▶Isoniaziddecreases the effects oflevodopa.oStudy
▶Isoniazidis predicted to increase the exposure tolomitapide.
Separate administration by 12 hours.qTheoretical→
Also seeTABLE 1p. 847
▶Isoniazidis predicted to increase the risk of peripheral
neuropathy when given withstavudine.rTheoretical→
Also seeTABLE 12p. 850
▶Isoniazidis predicted to affect the clearance oftheophylline.
rAnecdotal
▶Isoniazidpotentially increases the risk of nephrotoxicity when
given withvolatile halogenated anaesthetics(methoxyflurane).
Avoid.rTheoretical
Isosorbide dinitrate→see nitrates
Isosorbide mononitrate→see nitrates
Isotretinoin→see retinoids
Itraconazole→see antifungals, azoles
Ivabradine→seeTABLE 6p. 848 (bradycardia),TABLE 9p. 849 (QT-
interval prolongation)
▶Antiarrhythmics(dronedarone)are predicted to increase the
exposure toivabradine. Adjustivabradinedose.r
Theoretical
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to decrease the exposure
toivabradine. Adjust dose.oTheoretical
▶Antifungals, azoles(fluconazole, isavuconazole, posaconazole)
are predicted to increase the exposure toivabradine. Adjust
ivabradinedose.rTheoretical
▶Antifungals, azoles(itraconazole, ketoconazole, voriconazole)are
predicted to increase the exposure toivabradine. Avoid.
rStudy
▶Aprepitantis predicted to increase the exposure toivabradine.
Adjustivabradinedose.rTheoretical
▶Calcium channel blockers(diltiazem, verapamil)are predicted to
increase the exposure toivabradine. Avoid.oStudy→
Also seeTABLE 6p. 848
▶Cobicistatis predicted to increase the exposure toivabradine.
Avoid.rStudy
▶Crizotinibis predicted to increase the exposure toivabradine.
Adjustivabradinedose.rTheoretical→Also seeTABLE 6
p. 848
▶Enzalutamideis predicted to decrease the exposure to
ivabradine. Adjust dose.oTheoretical
▶Grapefruit juiceis predicted to increase the exposure to
ivabradine. Avoid.oStudy
▶HIV-protease inhibitorsare predicted to increase the exposure
toivabradine. Avoid.rStudy
▶Idelalisibis predicted to increase the exposure toivabradine.
Avoid.rStudy
▶Imatinibis predicted to increase the exposure toivabradine.
Adjustivabradinedose.rTheoretical
▶Macrolides(clarithromycin)are predicted to increase the
exposure toivabradine. Avoid.rStudy
▶Macrolides(erythromycin)are predicted to increase the
exposure toivabradine. Avoid.rTheoretical
▶Mitotaneis predicted to decrease the exposure toivabradine.
Adjust dose.oTheoretical
▶Netupitantis predicted to increase the exposure toivabradine.
Adjustivabradinedose.rTheoretical
▶Nilotinibis predicted to increase the exposure toivabradine.
Adjustivabradinedose.rTheoretical
▶Rifampicinis predicted to decrease the exposure toivabradine.
Adjust dose.oTheoretical
▶St John’s Wortdecreases the exposure toivabradine. Avoid.
oStudy
Ivacaftor
FOOD AND LIFESTYLEAvoid bitter (Seville) oranges as they are
predicted to increase the exposure to ivacaftor.▶Antiarrhythmics(dronedarone)are predicted to increase the
exposure toivacaftor. Adjustivacaftordose with moderate
inhibitors of CYP3A4,p. 186.rStudy
▶Antiepileptics(carbamazepine, fosphenytoin, phenobarbital,
phenytoin, primidone)are predicted to moderately to markedly
decrease the exposure toivacaftor. Avoid.rStudy
▶Antifungals, azoles(fluconazole, isavuconazole, posaconazole)
are predicted to increase the exposure toivacaftor. Adjust
ivacaftordose with moderate inhibitors of CYP3A4,p. 186.
rStudy
▶Antifungals, azoles(itraconazole, ketoconazole, voriconazole)are
predicted to increase the exposure toivacaftor. Adjust
ivacaftorp. 186orlumacaftor with ivacaftorp. 187dose with
potent inhibitors of CYP3A4.rStudy
▶Aprepitantis predicted to increase the exposure toivacaftor.
Adjustivacaftordose with moderate inhibitors of CYP3A4,
p. 186.rStudy
▶Bosentanis predicted to decrease the exposure toivacaftor.
rTheoretical
▶Calcium channel blockers(diltiazem, verapamil)are predicted to
increase the exposure toivacaftor. Adjustivacaftordose with
moderate inhibitors of CYP3A4,p. 186.rStudy
▶Cobicistatis predicted to increase the exposure toivacaftor.
Adjustivacaftorp. 186orlumacaftor with ivacaftorp. 187dose
with potent inhibitors of CYP3A4.rStudy
▶Ivacaftoris predicted to increase the anticoagulant effect of
coumarins(warfarin).rTheoretical
▶Crizotinibis predicted to increase the exposure toivacaftor.
Adjustivacaftordose with moderate inhibitors of CYP3A4,
p. 186.rStudy
▶Ivacaftorslightly increases the exposure todigoxin.o
Study
▶Efavirenzis predicted to decrease the exposure toivacaftor.
rTheoretical
▶Enzalutamideis predicted to moderately to markedly decrease
the exposure toivacaftor. Avoid.rStudy
▶Grapefruit juiceis predicted to increase the exposure to
ivacaftor. Avoid.oTheoretical
▶HIV-protease inhibitorsare predicted to increase the exposure
toivacaftor. Adjustivacaftorp. 186orlumacaftor with ivacaftor
p. 187dose with potent inhibitors of CYP3A4.rStudy
▶Idelalisibis predicted to increase the exposure toivacaftor.
Adjustivacaftorp. 186orlumacaftor with ivacaftorp. 187dose
with potent inhibitors of CYP3A4.rStudy
▶Imatinibis predicted to increase the exposure toivacaftor.
Adjustivacaftordose with moderate inhibitors of CYP3A4,
p. 186.rStudy
▶Ivacaftoris predicted to increase the exposure tolomitapide.
Separate administration by 12 hours.oTheoretical
▶Macrolides(clarithromycin)are predicted to increase the
exposure toivacaftor. Adjustivacaftorp. 186orlumacaftor with
ivacaftorp. 187dose with potent inhibitors of CYP3A4.r
Study
▶Macrolides(erythromycin)are predicted to increase the
exposure toivacaftor. Adjustivacaftordose with moderate
inhibitors of CYP3A4,p. 186.rStudy
▶Mitotaneis predicted to moderately to markedly decrease the
exposure toivacaftor. Avoid.rStudy
▶Netupitantis predicted to increase the exposure toivacaftor.
Adjustivacaftordose with moderate inhibitors of CYP3A4,
p. 186.rStudy
▶Nevirapineis predicted to decrease the exposure toivacaftor.
rTheoretical
▶Nilotinibis predicted to increase the exposure toivacaftor.
Adjustivacaftordose with moderate inhibitors of CYP3A4,
p. 186.rStudy
▶Rifampicinis predicted to moderately to markedly decrease
the exposure toivacaftor. Avoid.rStudy
▶St John’sWortis predicted to decrease the exposure to
ivacaftor.rTheoretical
Ivermectin
▶Ivermectinpotentially increases the anticoagulant effect of
coumarins.rAnecdotal
▶Levamisoleincreases the exposure toivermectin.o
StudyBNFC 2018 – 2019 Isoniazid—Ivermectin 939
Interactions|Appendix 1A1