glucose tolerance.insulin detemirMonitor Closely (1)ethinylestradiol decreases effects of insulin detemir by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.insulin glargineMonitor Closely (1)ethinylestradiol decreases effects of insulin glargine by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.insulin glulisineMonitor Closely (1)ethinylestradiol decreases effects of insulin glulisine by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.insulin inhaledMonitor Closely (2)norethindrone decreases effects of insulin inhaled by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance. ethinylestradiol decreases effects of insulin inhaled by pharmacodynamic antagonism. Use Caution/Monitor. Estrogens may impair glucose tolerance.insulin lisproMonitor Closely (1)ethinylestradiol decreases effects of insulin lispro by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.insulin NPHMonitor Closely (1)ethinylestradiol decreases effects of insulin NPH by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.insulin regular humanMonitor Closely (1)ethinylestradiol decreases effects of insulin regular human by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.isavuconazonium sulfateMonitor Closely (1)ethinylestradiol will increase the level or effect of isavuconazonium sulfate by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)isavuconazonium sulfate will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.istradefyllineMonitor Closely (2)istradefylline will increase the level or effect of norethindrone 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 ethinylestradiol 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.itraconazoleMonitor Closely (1)itraconazole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors such as itraconazole may increase plasma hormone levels.ivosidenibSerious - Use Alternative (2)ivosidenib will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternate therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs. ivosidenib will decrease the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternative therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs.ketoconazoleMonitor Closely (1)ketoconazole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors such as ketoconazole may increase plasma hormone levels.lamotrigineMonitor Closely (2)norethindrone will decrease the level or effect of lamotrigine by increasing hepatic clearance. Use Caution/Monitor. Combination oral contraceptives have been shown to significantly decrease plasma concentrations of lamotrigine, likely due to induction of lamotrigine glucuronidation. ethinylestradiol decreases levels of lamotrigine by increasing hepatic clearance. Use Caution/Monitor. Combination oral contraceptives have been shown to significantly decrease plasma concentrations of lamotrigine, likely due to induction of lamotrigine glucuronidation.lapatinibMonitor Closely (1)ethinylestradiol will increase the level or effect of lapatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.larotrectinibMinor (2)larotrectinib will increase the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. larotrectinib will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lemborexantMonitor Closely (1)ethinylestradiol will increase the level or effect of lemborexant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Lower nightly dose of lemborexant recommended if coadministered with weak CYP3A4 inhibitors. See drug monograph for specific dosage modification.lenacapavirMonitor Closely (2)lenacapavir will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lencapavir (a moderate CYP3A4 inhibitor) may increase CYP3A4 substrates initiated within 9 months after last SC dose of lenacapavir, which may increase potential risk of adverse reactions of CYP3A4 substrates. lenacapavir will increase the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lencapavir may increase CYP3A4 substrates initiated within 9 months after last SC dose of lenacapavir, which may increase potential risk of adverse reactions of CYP3A4 substrates.leniolisibSerious - Use Alternative (1)leniolisib will increase the level or effect of ethinylestradiol by Other (see comment). Avoid or Use Alternate Drug. Leniolisib, a BCRP inhibitor, may increase systemic exposure of BCRP substrateslesinuradSerious - Use Alternative (2)lesinurad decreases effects of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Use additional methods of nonhormonal contraception. Do not rely on hormonal contraception alone when taking lesinurad. lesinurad decreases effects of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Use additional methods of nonhormonal contraception. Do not rely on hormonal contraception alone when taking lesinurad.letermovirMonitor Closely (1)letermovir increases levels of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.letrozoleSerious - Use Alternative (1)ethinylestradiol decreases effects of letrozole by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Letrozole should not be given concurrently with any estrogens or estrogen-containing products.levofloxacinMonitor Closely (1)levofloxacin will decrease the level or effect of ethinylestradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.levoketoconazoleMonitor Closely (1)levoketoconazole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors such as ketoconazole may increase plasma hormone levels.Minor (1)levoketoconazole will increase the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.liraglutideMonitor Closely (1)ethinylestradiol decreases effects of liraglutide by pharmacodynamic antagonism. Use Caution/Monitor. Oral contraceptives may decrease hypoglycemic effects of antidiabetics by impairing glucose tolerance. Monitor for glycemic control in diabetic patients.lixisenatide (DSC)Monitor Closely (1)lixisenatide (DSC) will decrease the level or effect of ethinylestradiol by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. GLP1 agonists delay gastric emptying, which may affect absorption of concomitantly administered oral medications. Oral contraceptives should be taken at least 1 hr before lixisenatide administration or 11 hr after lixisenatide.lomitapideMonitor Closely (1)ethinylestradiol increases levels of lomitapide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lomitapide dose should not exceed 30 mg/day.lonafarnibSerious - Use Alternative (1)ethinylestradiol will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. If coadministration of lonafarnib (a sensitive CYP3A substrate) with weak CYP3A inhibitors is unavoidable, reduce to, or continue lonafarnib at starting dose. Closely monitor for arrhythmias and events (eg, syncope, heart palpitations) since lonafarnib effect on QT interval is unknown.lonapegsomatropinMonitor Closely (2)ethinylestradiol will decrease the level or effect of lonapegsomatropin by Other (see comment). Use Caution/Monitor. Oral estrogens may reduce serum insulin-like growth factor-1 response to lonapegsomatropin. Patients receiving oral estrogen replacement may require higher lonapegsomatropin dosages. ethinylestradiol will decrease the level or effect of lonapegsomatropin by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Oral estrogens may reduce serum insulin-like growth factor I (IGF-1) response to growth hormone (GH) analogs. Higher GH dose may be requiredlopinavirMonitor Closely (1)lopinavir will increase the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (2)lopinavir will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. lopinavir, ethinylestradiol. Other (see comment). Avoid or Use Alternate Drug. Comment: Significant changes (increase or decrease) can occur in estrogen plasma levels. Efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended. .lorlatinibMonitor Closely (1)lorlatinib will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Serious - Use Alternative (1)lorlatinib will decrease the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Monitor response to estrogens and progestins whenever a CYP3A4 inducer is added to or discontinued, and adjust hormone dosage as necessary. For adequate protection against conception, advise additional or alternative nonhormonal birth control during coadministration with CY3A4 inducers and beyond discontinuation of the CYP3A4 inducers for ~for 3 plasma half-lives.lumacaftor/ivacaftorSerious - Use Alternative (2)lumacaftor/ivacaftor will decrease the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration unless benefit outweighs risk. 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). lumacaftor/ivacaftor will decrease the level or effect of ethinylestradiol by unspecified interaction mechanism. Avoid or Use Alternate Drug. Avoid coadministration unless benefit outweighs risk. 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).lumefantrineMonitor Closely (1)lumefantrine will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.maravirocMonitor Closely (1)norethindrone increases levels of maraviroc by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Potential for increased toxicity.mavacamtenSerious - Use Alternative (2)mavacamten will decrease the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Progestin and ethinyl estradiol are CYP3A4 substrates. Mavacamten may decrease systemic exposures of ethinyl estradiol and progestin, which may lead to contraceptive failure or an increase in breakthrough bleeding. Advise patients to use a contraceptive method that is not affected by CYP450 enzyme induction (eg, intrauterine system) or add nonhormonal contraception (eg, condoms) during coadministration and for 4 months after last mavacamten dose. mavacamten will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Progestin and ethinyl estradiol are CYP3A4 substrates. Mavacamten may decrease systemic exposures of ethinyl estradiol and progestin, which may lead to contraceptive failure or an increase in breakthrough bleeding. Advise patients to use a contraceptive method that is not affected by CYP450 enzyme induction (eg, intrauterine system) or add nonhormonal contraception (eg, condoms) during coadministration and for 4 months after last mavacamten dose.metforminMonitor Closely (2)ethinylestradiol decreases effects of metformin by pharmacodynamic antagonism. Use Caution/Monitor. norethindrone decreases effects of metformin by pharmacodynamic antagonism. Use Caution/Monitor.metronidazoleMonitor Closely (1)metronidazole will decrease the level or effect of ethinylestradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.metyraponeSerious - Use Alternative (1)ethinylestradiol decreases effects of metyrapone by unspecified interaction mechanism. Avoid or Use Alternate Drug. A subtherapeutic response to metyrapone can be seen in patients on estrogens, including oral contraceptives, that contain estrogen therapy. It may be advisable to discontinue estrogens prior to and during metyrapone administration.mexiletineMonitor Closely (1)ethinylestradiol will increase the level or effect of mexiletine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.midazolamMonitor Closely (1)ethinylestradiol will increase the level or effect of midazolam by Mechanism: decreasing metabolism. Use Caution/Monitor. Ethinyl estradiol may inhibit the clearance of benzodiazepines that undergo oxidation, thereby increasing serum concentrations of concomitantly administered benzodiazepines.midazolam intranasalMonitor Closely (1)ethinylestradiol will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Coadministration of mild CYP3A4 inhibitors with midazolam intranasal may cause higher midazolam systemic exposure, which may prolong sedation.mifepristoneContraindicated (1)mifepristone will increase the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Contraindicated.Monitor Closely (2)mifepristone decreases effects of norethindrone by pharmacodynamic antagonism. Use Caution/Monitor. Backup contraceptive method recommended. mifepristone decreases effects of ethinylestradiol by pharmacodynamic antagonism. Use Caution/Monitor. Backup contraceptive method recommended.Serious - Use Alternative (1)mifepristone will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.mineral oilMinor (1)mineral oil decreases levels of ethinylestradiol by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.minocyclineMonitor Closely (1)minocycline will decrease the level or effect of ethinylestradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Use Caution/Monitor.mitotaneMonitor Closely (1)mitotane decreases levels of ethinylestradiol 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