needed.ribociclibelagolix decreases levels of ribociclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.ribociclib will increase the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifabutinrifabutin will decrease the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.elagolix decreases levels of rifabutin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.rifampinrifampin will increase the level or effect of elagolix by Other (see comment). Modify Therapy/Monitor Closely. Limit concomitant use of elagolix 150 mg qDay and rifampin to 6 months.elagolix will increase the level or effect of rifampin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.rifampin will decrease the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Limit concomitant use of elagolix 150 mg qDay and rifampin to 6 months.rifapentinerifapentine will decrease the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifaximinelagolix will increase the level or effect of rifaximin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.riociguatelagolix will increase the level or effect of riociguat by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.elagolix decreases levels of riociguat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.ripretinibelagolix will decrease the level or effect of ripretinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. If coadministration cannot be avoided, increase dosing frequency from recommended dose of 150 mg once daily to 150 mg twice daily during co-administration period; monitor for clinical response and tolerabilityrisperidoneelagolix will increase the level or effect of risperidone by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.ritonavirelagolix will increase the level or effect of ritonavir by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.elagolix decreases levels of ritonavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.rivaroxabanelagolix decreases levels of rivaroxaban by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.roflumilastelagolix decreases levels of roflumilast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.rolapitantelagolix decreases levels of rolapitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.romidepsinelagolix decreases levels of romidepsin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.ropivacaineelagolix decreases levels of ropivacaine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.rosuvastatinelagolix decreases levels of rosuvastatin by unknown mechanism. Modify Therapy/Monitor Closely. Consider increasing the dose of rosuvastatin.rucaparibrucaparib will increase the level or effect of norethindrone acetate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.rucaparib will increase the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.mitotanemitotane decreases levels of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.ruxolitinibelagolix decreases levels of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.moxifloxacinmoxifloxacin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.nafcillinnafcillin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.nafcillin will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nefazodonenefazodone will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.nelfinavirnelfinavir will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.neomycin POneomycin PO will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.nevirapinenevirapine will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nicardipinenicardipine will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.nifedipinenifedipine will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nifedipine will decrease the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.nilotinibnilotinib will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nilotinib will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.nitrofurantoinnitrofurantoin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.ofloxacinofloxacin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.oxcarbazepineoxcarbazepine will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.oxytetracyclineoxytetracycline will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.paromomycinparomomycin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.pentobarbitalpentobarbital will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.phenobarbitalphenobarbital will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.phenobarbital will decrease the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.phenytoinphenytoin will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.phenytoin will decrease the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.pivmecillinampivmecillinam will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.ponatinibponatinib increases levels of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.posaconazoleposaconazole will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.prednisoneprednisone will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.primidoneprimidone will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.quercetinquercetin will decrease the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.quinupristin/dalfopristinquinupristin/dalfopristin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.quinupristin/dalfopristin will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ranolazineranolazine will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.ribociclibribociclib will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifampinrifampin will decrease the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.rifapentinerifapentine will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ritonavirritonavir will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ritonavir will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.roxithromycinroxithromycin will decrease the level or effect of estradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Modify Therapy/Monitor Closely.rufinamiderufinamide decreases effects of norethindrone acetate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Rufinamide is a weak inducer of the CYP 3A4 enzyme and can decrease exposure of drugs that are substrates of CYP3A4. .rufinamide will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ruxolitinib topicalelagolix decreases levels of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.salmeterolelagolix decreases levels of salmeterol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.saquinavirelagolix will increase the level or effect of saquinavir by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.saquinavir will increase the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration of elagolix 200 mg BID with strong CYP3A inhibitors for >1 month is not recommended. Limit elagolix dose to 150 mg qDay and CYP3A inhibitor duration of use to 6 months if coadministered.elagolix decreases levels of saquinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.saxagliptinelagolix will increase the level or effect of saxagliptin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.elagolix decreases levels of saxagliptin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.secobarbitalsecobarbital will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.secobarbital will decrease the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.sildenafilelagolix decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.siltuximabsiltuximab, norethindrone acetate. Other (see comment). Use Caution/Monitor. Comment: CYP450 activity in the liver is down regulated by infection and inflammation stimuli including cytokines (eg, IL-6); inhibition of IL-6 by siltuximab may restore CYP450 enzymatic activity; caution if coadministered with CYP substrates that have a narrow therapeutic index.silodosinelagolix will increase the level or effect of silodosin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.simvastatinsimvastatin will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.elagolix decreases levels of simvastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.elagolix will increase the level or effect of simvastatin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.siponimodelagolix decreases levels of siponimod by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.sirolimussirolimus will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.sirolimuselagolix will increase the level or effect of sirolimus by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.elagolix decreases levels of sirolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.sitagliptinelagolix will increase the level or effect of sitagliptin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.sofosbuvirelagolix will increase the level or effect of sofosbuvir by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.sofosbuvir/velpatasvirelagolix decreases levels of sofosbuvir/velpatasvir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.solifenacinelagolix decreases levels of solifenacin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.somapacitanestradiol decreases effects of somapacitan by Other (see comment). Modify Therapy/Monitor Closely. Comment: Oral estrogens may reduce the serum IGF-1 response to somapacitan. Patients may require higher somapacitan dosages. See drug monograph for starting dose recommendations.St John's WortSt John's Wort will decrease the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.sonidegibelagolix decreases levels of sonidegib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.sorafenibelagolix decreases levels of sorafenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer.