while increasing TCA plasma concentration and adverse effects.amoxicillinMonitor Closely (1)amoxicillin 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. Antibiotics may decrease hormonal contraceptive efficacy.ampicillinMonitor Closely (1)ampicillin 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.anastrozoleSerious - Use Alternative (1)ethinylestradiol decreases effects of anastrozole by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Anastrozole should not be given concurrently with any estrogens or estrogen-containing products.Minor (1)anastrozole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.antipyrineMinor (1)ethinylestradiol will increase the level or effect of antipyrine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.apalutamideSerious - Use Alternative (1)apalutamide will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of apalutamide, a strong CYP3A4 inducer, with drugs that are CYP3A4 substrates can result in lower exposure to these medications. Avoid or substitute another drug for these medications when possible. Evaluate for loss of therapeutic effect if medication must be coadministered. Adjust dose according to prescribing information if needed.armodafinilSerious - Use Alternative (1)armodafinil will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.artemether/lumefantrineMonitor Closely (1)artemether/lumefantrine will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.asenapineMinor (1)ethinylestradiol will increase the level or effect of asenapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.atazanavirMonitor Closely (1)atazanavir, desogestrel. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Atazanavir may increase or decrease levels of desogestrel. Use alternatives if available.Serious - Use Alternative (1)atazanavir, 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. .atogepantMonitor Closely (1)ethinylestradiol will increase the level or effect of atogepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.atorvastatinMonitor Closely (1)atorvastatin will increase the level or effect of ethinylestradiol by P-glycoprotein (MDR1) efflux transporter. Use Caution/Monitor.axitinibMonitor Closely (1)ethinylestradiol increases levels of axitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.belzutifanSerious - Use Alternative (1)belzutifan will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Coadministration of belzutifan with hormonal contraceptives may lead to contraceptive failure or increased breakthrough bleeding. Advise females of reproductive potential to use effective nonhormonal contraception. Based on animal studies, belzutifan can cause fetal harm.bendamustineMonitor Closely (1)ethinylestradiol increases levels of bendamustine by decreasing metabolism. Use Caution/Monitor. Bendamustine is metabolized to minimally active metabolites by CYP1A2. Ethinyl estradiol is a weak CYP1A2 inhibitor and concurrent administration may increase bendamustine concentrations in plasma. .bosentanSerious - Use Alternative (1)bosentan will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.brigatinibSerious - Use Alternative (1)brigatinib will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Brigatinib induces CYP3A4 in vitro. Coadministration of hormonal contraceptives with brigatinib can result in decreased concentrations and loss of efficacy. Brigatinib can cause fetal harm. Women should use an effective nonhormonal method of contraception during treatment and for at least 4 months after the last brigatinib dose.butabarbitalSerious - Use Alternative (1)butabarbital will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.cabotegravirContraindicated (1)desogestrel will decrease the level or effect of cabotegravir by increasing metabolism. Contraindicated. Cabotegravir is metabolized by UGT1A1 and UGT1A9. Strong UGT1A1 or UGT1A9 inducers decrease cabotegravir systemic exposure, thereby increasing potential for loss of virologic response.caffeineMonitor Closely (1)ethinylestradiol will increase the level or effect of caffeine by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.calaspargase pegolSerious - Use Alternative (1)calaspargase pegol, ethinylestradiol. unknown mechanism. Avoid or Use Alternate Drug. Due to the potential for an indirect interaction between calaspargase pegol and oral contraceptives, concomitant use of these drugs is not recommended. Use another non-oral contraceptive method for females of childbearing potential.carbamazepineMonitor Closely (1)carbamazepine will decrease the level or effect of desogestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Advise patients to use alternative contraceptive method during coadministration; continue alternative contraception for 28 days after discontinuing therapy to ensure contraception reliability Serious - Use Alternative (2)ethinylestradiol will increase the level or effect of carbamazepine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended. carbamazepine will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.cefaclorMonitor Closely (1)cefaclor 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.cefadroxilMonitor Closely (1)cefadroxil 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.cefazolinMonitor Closely (1)cefazolin 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.cefdinirMonitor Closely (1)cefdinir 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.cefepimeMonitor Closely (1)cefepime 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.cefiximeMonitor Closely (1)cefixime 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.cefotaximeMonitor Closely (1)cefotaxime 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.cefprozilMonitor Closely (1)cefprozil 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.ceftazidimeMonitor Closely (1)ceftazidime 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.ceftibutenMonitor Closely (1)ceftibuten 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.cefuroximeMonitor Closely (1)cefuroxime 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.cenobamateMonitor Closely (2)cenobamate will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate. cenobamate will decrease the level or effect of ethinylestradiol by unspecified interaction mechanism. Modify Therapy/Monitor Closely. Advise women to use additional or alternative non-hormonal birth control when concomitantly using cenobamate with oral contraceptives.cephalexinMonitor Closely (1)cephalexin 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.ceritinibMonitor Closely (1)ceritinib will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.chloramphenicolMonitor Closely (1)chloramphenicol 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.cimetidineMonitor Closely (1)cimetidine will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ciprofloxacinMonitor Closely (1)ciprofloxacin 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.clarithromycinMonitor Closely (1)clarithromycin will decrease the level or effect of ethinylestradiol by altering intestinal flora. Applies only to oral forms of hormone. Low risk of contraceptive failure. Modify Therapy/Monitor Closely.Minor (1)ethinylestradiol will increase the level or effect of clarithromycin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.clindamycinMonitor Closely (1)clindamycin 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.clobazamMonitor Closely (2)clobazam will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Clobazam is a weak CYP3A4 inducer; effectiveness of hormonal contraceptives may be diminished when given concurrently with clobazam. Additional non-hormonal forms of contraception are recommended. clobazam will decrease the level or effect of desogestrel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Clobazam is a weak CYP3A4 inducer; effectiveness of hormonal contraceptives may be diminished when given concurrently with clobazam. Additional non-hormonal forms of contraception are recommended.clomipramineMinor (1)ethinylestradiol will increase the level or effect of clomipramine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.clonazepamMonitor Closely (1)ethinylestradiol will increase the level or effect of clonazepam 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.conivaptanSerious - Use Alternative (1)conivaptan will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.cyclophosphamideMinor (1)cyclophosphamide will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.cyclosporineMonitor Closely (1)ethinylestradiol increases levels of cyclosporine by unknown mechanism. Use Caution/Monitor.dabrafenibMonitor Closely (1)dabrafenib will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.darunavirMonitor Closely (1)darunavir will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. 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. dasatinibMonitor Closely (1)ethinylestradiol will increase the level or effect of dasatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.deferasiroxMonitor Closely (1)deferasirox will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.demeclocyclineMonitor Closely (1)demeclocycline 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.desipramineMinor (1)ethinylestradiol, desipramine. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Oxidative metabolism of TCAs may be decreased by ethinyl estradiol. Increased antidepressant serum concentrations may occur. Potential for increased TCA adverse effects.dexamethasoneSerious - Use Alternative (1)dexamethasone will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.diazepamMonitor Closely (1)ethinylestradiol will increase the level or effect of diazepam 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.dicloxacillinMonitor Closely (1)dicloxacillin 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.dosulepinMinor (1)ethinylestradiol, dosulepin. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Oxidative metabolism of TCAs may be decreased by ethinyl estradiol. Increased antidepressant serum concentrations may occur. Potential for increased TCA adverse effects.doxepinMinor (1)ethinylestradiol, doxepin. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Oxidative metabolism of TCAs may be decreased by ethinyl estradiol. Increased antidepressant serum concentrations may occur. Potential for increased TCA adverse effects.doxycyclineMonitor Closely (1)doxycycline 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.duloxetineMinor (1)ethinylestradiol will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.efavirenzSerious - Use Alternative (1)efavirenz will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. The efficacy of hormonal contraceptives may be reduced. Use of a nonhormonal contraceptive is recommended.elagolixMonitor Closely (1)elagolix will decrease the level or effect of ethinylestradiol 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 (1)ethinylestradiol decreases effects of elagolix by pharmacodynamic antagonism. Avoid or Use Alternate Drug. Based on the mechanism of action of elagolix, estrogen-containing