lead to increased seizure frequencyvonoprazanvonoprazan will decrease the level or effect of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor.voriconazolevoriconazole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (42)acetazolamideacetazolamide will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.acetohydroxamic acidacetohydroxamic acid decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.amitriptylineethinylestradiol, amitriptyline. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.amoxapineethinylestradiol, amoxapine. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.anastrozoleanastrozole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.antipyrineethinylestradiol will increase the level or effect of antipyrine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.asenapineethinylestradiol will increase the level or effect of asenapine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.calcium acetatecalcium acetate decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ferrous fumarate increases levels of calcium acetate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.calcium carbonatecalcium carbonate decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ferrous fumarate increases levels of calcium carbonate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.calcium chloridecalcium chloride decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ferrous fumarate increases levels of calcium chloride by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.calcium citratecalcium citrate decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ferrous fumarate increases levels of calcium citrate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.calcium gluconatecalcium gluconate decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.ferrous fumarate increases levels of calcium gluconate by enhancing GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.carbidopaferrous fumarate decreases levels of carbidopa by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.clarithromycinethinylestradiol will increase the level or effect of clarithromycin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.clomipramineethinylestradiol will increase the level or effect of clomipramine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.cyclophosphamidecyclophosphamide will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.desipramineethinylestradiol, 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.didanosinedidanosine will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Minor/Significance Unknown. Applies to didanosine chewable tablets and powder for oral solution; administer 2 hr before or several hours after didanosine oral solution or chewable tablet administrationdosulepinethinylestradiol, 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.doxepinethinylestradiol, 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.duloxetineethinylestradiol will increase the level or effect of duloxetine by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.enasidenibenasidenib, ethinylestradiol. unknown mechanism. Minor/Significance Unknown. Coadministration of enasidenib may increase or decrease the concentrations of combined hormonal contraceptives. Clinical significance of this interaction is unknown.eplerenoneethinylestradiol will increase the level or effect of eplerenone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.felbamatefelbamate decreases levels of ethinylestradiol by unknown mechanism. Minor/Significance Unknown.frovatriptanethinylestradiol will increase the level or effect of frovatriptan by affecting hepatic enzyme CYP1A2 metabolism. Minor/Significance Unknown.gymnemagymnema decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.imipramineethinylestradiol, imipramine. 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.larotrectiniblarotrectinib will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.manganeseferrous fumarate decreases levels of manganese by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.mineral oilmineral oil decreases levels of ethinylestradiol by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.naratriptanethinylestradiol increases effects of naratriptan by unspecified interaction mechanism. Minor/Significance Unknown. The clinical implication of these interactions is unknown.nefazodonenefazodone will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nortriptylineethinylestradiol, nortriptyline. 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.protriptylineethinylestradiol, protriptyline. 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.ramelteonethinylestradiol will increase the level or effect of ramelteon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rosuvastatinrosuvastatin increases levels of ethinylestradiol by unspecified interaction mechanism. Minor/Significance Unknown.ruxolitinibethinylestradiol will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ruxolitinib topicalethinylestradiol will increase the level or effect of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.tizanidineethinylestradiol increases levels of tizanidine by unspecified interaction mechanism. Minor/Significance Unknown.trazodoneethinylestradiol, trazodone. 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.trimipramineethinylestradiol, trimipramine. 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.vitamin Evitamin E decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.abametapirSerious - Use Alternative (1)abametapir will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For 2 weeks after abametapir application, avoid taking drugs that are CYP3A4 substrates. If not feasible, avoid use of abametapir.acetazolamideMinor (1)acetazolamide will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.acetohydroxamic acidMinor (1)acetohydroxamic acid decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Minor/Significance Unknown.albiglutideMonitor Closely (1)ethinylestradiol decreases effects of albiglutide 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.alosetronMonitor Closely (1)ethinylestradiol will increase the level or effect of alosetron by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.alprazolamMonitor Closely (1)ethinylestradiol will increase the level or effect of alprazolam 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.aluminum hydroxideMonitor Closely (1)aluminum hydroxide will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.aminocaproic acidMonitor Closely (1)ethinylestradiol, aminocaproic acid. Other (see comment). Use Caution/Monitor. Comment: Concomitant use may lead to additive hypercoagulability. Estrogens increase clotting factor production and platelet aggregation; aminocaproic acid inhibits fibrinolysis and activity of plasminogen.amitriptylineMinor (1)ethinylestradiol, amitriptyline. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, while increasing TCA plasma concentration and adverse effects.amobarbitalSerious - Use Alternative (1)amobarbital 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.amoxapineMinor (1)ethinylestradiol, amoxapine. Mechanism: unspecified interaction mechanism. Minor/Significance Unknown. Estrogens and progestins may decr tricyclic antidepressant effects, 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.atazanavirSerious - 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.baloxavir marboxilSerious - Use Alternative (1)ferrous fumarate will decrease the level or effect of baloxavir marboxil by cation binding in GI tract. Avoid or Use Alternate Drug. Baloxavir may bind to polyvalent cations resulting in decreased absorption. Studies in monkeys showed concurrent use with calcium, aluminum, or iron caused significantly decreased plasma levels. Human studies not conducted.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. .bictegravirMonitor Closely (1)ferrous fumarate will decrease the level or effect of bictegravir by cation binding in GI tract. Modify Therapy/Monitor Closely. Bictegravir and supplements containing iron can be taken together with food. Routine administration of bictegravir (under fasting conditions) simultaneously with, or 2 hr after, supplements containing iron is not recommended.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.caffeineMonitor Closely (1)ethinylestradiol will increase the level or effect of