When coadministered, hormonal contraceptives are not a reliable method of effective birth control. Concomitant use may increase incidence of menstruation associated adverse effects (amenorrhea, dysmenorrhea, menorrhagia).fostamatinibMonitor Closely (1)fostamatinib will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. Concomitant use of fostamatinib may increase concentrations of P-gp substrates. Monitor for toxicities of the P-gp substrate drug that may require dosage reduction when given concurrently with fostamatinib.fostemsavirMonitor Closely (1)fostemsavir will increase the level or effect of elagolix by Other (see comment). Modify Therapy/Monitor Closely. Fostemsavir inhibits OATP1B1/3 transporter. If possible, avoid coadministration or modify dose of OATP1B1/3 substrates coadministered with fostemsavir. ganaxoloneSerious - Use Alternative (1)elagolix will decrease the level or effect of ganaxolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of ganaxolone with moderate or strong CYP3A4 inducers. If coadministration unavoidable, consider increasing ganaxolone dose; however, do not exceed maximum daily dose for weight.gefitinibMonitor Closely (1)elagolix decreases levels of gefitinib 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.gemfibrozilContraindicated (1)gemfibrozil will increase the level or effect of elagolix by Other (see comment). Contraindicated. Concomitant use of elagolix and strong OATP1B1 inhibitors is contraindicated.gemifloxacinMonitor Closely (1)gemifloxacin 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.gentamicinMonitor Closely (1)gentamicin 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.givosiranSerious - Use Alternative (1)givosiran will increase the level or effect of estradiol by affecting hepatic enzyme CYP1A2 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP1A2 substrates with givosiran. If unavoidable, decrease the CYP1A2 substrate dosage in accordance with approved product labeling.glasdegibMonitor Closely (1)elagolix decreases levels of glasdegib 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.glecaprevir/pibrentasvirContraindicated (1)glecaprevir/pibrentasvir will increase the level or effect of elagolix by Other (see comment). Contraindicated. Concomitant use of elagolix and strong OATP1B1 inhibitors is contraindicated.Monitor Closely (3)glecaprevir/pibrentasvir will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. elagolix will increase the level or effect of glecaprevir/pibrentasvir by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. elagolix decreases levels of glecaprevir/pibrentasvir 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.grapefruitMonitor Closely (1)grapefruit will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)grapefruit will increase the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.griseofulvinMonitor Closely (1)griseofulvin will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.guanfacineMonitor Closely (1)elagolix decreases levels of guanfacine 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.haloperidolMonitor Closely (1)elagolix decreases levels of haloperidol 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.heminMonitor Closely (1)estradiol decreases effects of hemin by pharmacodynamic antagonism. Use Caution/Monitor. Drugs that increase delta-aminolevulinic acid synthetase may decrease hemin effect.heparinSerious - Use Alternative (1)estradiol decreases effects of heparin by pharmacodynamic antagonism. Contraindicated. Risk of thromboembolic disorders.hyaluronidaseMonitor Closely (1)estradiol decreases effects of hyaluronidase by Other (see comment). Use Caution/Monitor. Comment: Estrogens, when given in large systemic doses, may render tissues partially resistant to the action of hyaluronidase. Patients may require larger amounts of hyaluronidase for equivalent dispersing effect.hydrocodoneMonitor Closely (1)elagolix decreases levels of hydrocodone 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.hydrocortisoneMonitor Closely (2)elagolix will increase the level or effect of hydrocortisone by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. hydrocortisone will decrease the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.hydroxyprogesterone caproate (DSC)Monitor Closely (1)elagolix decreases levels of hydroxyprogesterone caproate (DSC) 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.ibrutinibMonitor Closely (1)elagolix decreases levels of ibrutinib 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.idarubicinMonitor Closely (1)elagolix will increase the level or effect of idarubicin by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.idelalisibMonitor Closely (2)idelalisib 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 idelalisib 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.Serious - Use Alternative (2)idelalisib will increase the level or effect of norethindrone acetate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates idelalisib will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substratesifosfamideMonitor Closely (2)elagolix will increase the level or effect of ifosfamide by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak CYP2C19 inhibitor. Caution with sensitive CYP2C19 substrates. elagolix decreases levels of ifosfamide 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.iloperidoneMonitor Closely (2)iloperidone increases levels of norethindrone acetate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4. iloperidone increases levels of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4.imatinibMonitor Closely (2)elagolix will increase the level or effect of imatinib by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. elagolix decreases levels of imatinib 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.imipramineMonitor Closely (1)elagolix will increase the level or effect of imipramine by affecting hepatic enzyme CYP2C19 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak CYP2C19 inhibitor. Caution with sensitive CYP2C19 substrates.Minor (1)estradiol, imipramine. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.indinavirMonitor Closely (5)indinavir 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. indinavir will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. elagolix decreases levels of indinavir 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. indinavir will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. elagolix will increase the level or effect of indinavir by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.infigratinibSerious - Use Alternative (1)elagolix will decrease the level or effect of infigratinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.insulin degludecMonitor Closely (2)estradiol decreases effects of insulin degludec by pharmacodynamic antagonism. Use Caution/Monitor. Estrogens may impair glucose tolerance. norethindrone acetate decreases effects of insulin degludec by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.insulin degludec/insulin aspartMonitor Closely (2)norethindrone acetate decreases effects of insulin degludec/insulin aspart by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance. estradiol decreases effects of insulin degludec/insulin aspart by pharmacodynamic antagonism. Use Caution/Monitor. Estrogens may impair glucose tolerance.insulin inhaledMonitor Closely (2)estradiol decreases effects of insulin inhaled by pharmacodynamic antagonism. Use Caution/Monitor. Estrogens may impair glucose tolerance. norethindrone acetate decreases effects of insulin inhaled by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.irinotecanMonitor Closely (2)elagolix will increase the level or effect of irinotecan by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. elagolix decreases levels of irinotecan 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.irinotecan liposomalMonitor Closely (2)elagolix will increase the level or effect of irinotecan liposomal by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. elagolix decreases levels of irinotecan liposomal 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.isavuconazonium sulfateMonitor Closely (1)elagolix will decrease the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.isoniazidMonitor Closely (1)isoniazid 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.Minor (1)isoniazid will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.isosorbide dinitrateMonitor Closely (1)elagolix decreases levels of isosorbide dinitrate 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.isosorbide mononitrateMonitor Closely (1)elagolix decreases levels of isosorbide mononitrate 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.isradipineMonitor Closely (1)elagolix decreases levels of isradipine 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.istradefyllineMonitor Closely (4)istradefylline will increase the level or effect of norethindrone acetate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates. istradefylline will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates. istradefylline will increase the level or effect of elagolix by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates. elagolix decreases levels of istradefylline 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.itraconazoleMonitor Closely (4)itraconazole will increase the level or effect of estradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor. itraconazole will increase the level or effect of estradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. elagolix decreases levels of itraconazole 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. itraconazole 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.ivabradineMonitor Closely (1)elagolix decreases levels of ivabradine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer.