Closely (1)oteseconazole will increase the level or effect of ethinylestradiol by Other (see comment). Modify Therapy/Monitor Closely. Otesezonale, a BCRP inhibitor, may increase the effects and risk of toxicities of BCRP substrates. Use lowest starting dose of BCRP substrate, or consider reducing BCRP substrate dose.oxcarbazepineSerious - Use Alternative (1)oxcarbazepine 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.oxytetracyclineSerious - Use Alternative (1)ferrous fumarate decreases levels of oxytetracycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.pancrelipaseMonitor Closely (1)pancrelipase decreases levels of ferrous fumarate by enhancing GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Levels of iron salts may decrease with concomitant administration of digestive enzymes.pantoprazoleMonitor Closely (1)pantoprazole will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.paromomycinMonitor Closely (1)paromomycin 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.penicillamineMonitor Closely (1)ferrous fumarate decreases levels of penicillamine by inhibition of GI absorption. Applies only to oral form of both agents. Use Caution/Monitor. Interaction only with oral iron administration.penicillin G aqueousMonitor Closely (1)penicillin G aqueous decreases levels of ethinylestradiol by increasing metabolism. Use Caution/Monitor. Risk of oral contraceptive failure.penicillin VKMonitor Closely (1)penicillin VK 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.pentobarbitalSerious - Use Alternative (1)pentobarbital 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.phenobarbitalSerious - Use Alternative (1)phenobarbital 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.phenytoinSerious - Use Alternative (1)phenytoin 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.pioglitazoneMonitor Closely (1)pioglitazone decreases levels of ethinylestradiol by unknown mechanism. Use Caution/Monitor.posaconazoleMonitor Closely (1)posaconazole will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.primidoneSerious - Use Alternative (1)primidone 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.protriptylineMinor (1)ethinylestradiol, 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.quinidineSerious - Use Alternative (1)quinidine will increase the level or effect of ethinylestradiol by P-glycoprotein (MDR1) efflux transporter. Avoid or Use Alternate Drug.quinupristin/dalfopristinMonitor Closely (1)quinupristin/dalfopristin will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rabeprazoleMonitor Closely (1)rabeprazole will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.ramelteonMonitor Closely (1)ethinylestradiol will increase the level or effect of ramelteon by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.Minor (1)ethinylestradiol will increase the level or effect of ramelteon by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ranolazineSerious - Use Alternative (1)ethinylestradiol will increase the level or effect of ranolazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.rasagilineMonitor Closely (1)ethinylestradiol will increase the level or effect of rasagiline by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. Recommended dose of rasagiline is 0.5mg daily in combination with CYP1A2 inhibitors.ribociclibMonitor Closely (1)ribociclib will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifabutinSerious - Use Alternative (1)rifabutin 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.rifampinSerious - Use Alternative (1)rifampin 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.rifapentineSerious - Use Alternative (1)rifapentine 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.ritonavirSerious - Use Alternative (2)ritonavir will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. ritonavir, 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. .romidepsinMonitor Closely (1)romidepsin decreases effects of ethinylestradiol by receptor binding competition. Use Caution/Monitor.ropiniroleMonitor Closely (2)ethinylestradiol will increase the level or effect of ropinirole by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor. ethinylestradiol increases levels of ropinirole by unspecified interaction mechanism. Use Caution/Monitor.rosuvastatinMinor (1)rosuvastatin increases levels of ethinylestradiol by unspecified interaction mechanism. Minor/Significance Unknown.rucaparibMonitor Closely (1)rucaparib will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.rufinamideMonitor Closely (1)rufinamide decreases effects of ethinylestradiol 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. .ruxolitinibMinor (1)ethinylestradiol will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ruxolitinib topicalMinor (1)ethinylestradiol will increase the level or effect of ruxolitinib topical by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.saquinavirSerious - Use Alternative (2)saquinavir will increase the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. saquinavir, 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. .sarecyclineMonitor Closely (1)ferrous fumarate will decrease the level or effect of sarecycline by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Multivalent cation-containing products may impair absorption of tetracyclines, which may decrease its efficacy. Separate dosing of tetracyclines from these products.secobarbitalSerious - Use Alternative (1)secobarbital 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.selegilineMonitor Closely (1)ethinylestradiol increases levels of selegiline by Other (see comment). Use Caution/Monitor. Comment: Oral contraceptives inhibit the N demethylatin of selegiline.selegiline transdermalMonitor Closely (1)ethinylestradiol increases levels of selegiline transdermal by Other (see comment). Use Caution/Monitor. Comment: Oral contraceptives inhibit the N demethylatin of selegiline.siltuximabMonitor Closely (1)siltuximab, ethinylestradiol. 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.sodium bicarbonateMonitor Closely (1)sodium bicarbonate will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.sodium citrate/citric acidMonitor Closely (1)sodium citrate/citric acid will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Use Caution/Monitor.sodium picosulfate/magnesium oxide/anhydrous citric acidMonitor Closely (1)sodium picosulfate/magnesium oxide/anhydrous citric acid decreases levels of ferrous fumarate by cation binding in GI tract. Use Caution/Monitor. Take at least 2 hours before and not less than 6 hours after administration of sodium picosulfate, magnesium oxide and anhydrous citric acid to avoid magnesium chelation.sodium sulfate/?magnesium sulfate/potassium chlorideMonitor Closely (1)sodium sulfate/?magnesium sulfate/potassium chloride decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Administer iron products at least 2 hr before and no less than 6 hr after each dose to avoid chelation with magnesium. .sodium sulfate/potassium sulfate/magnesium sulfateMonitor Closely (1)sodium sulfate/potassium sulfate/magnesium sulfate decreases levels of ferrous fumarate by inhibition of GI absorption. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Administer iron products at least 2 hr before and no less than 6 hr after each dose to avoid chelation with magnesium. .sodium zirconium cyclosilicateMonitor Closely (1)sodium zirconium cyclosilicate will decrease the level or effect of ferrous fumarate by increasing gastric pH. Applies only to oral form of both agents. Modify Therapy/Monitor Closely. Check specific recommendations for drugs that exhibit pH-dependent solubility that may affect their systemic exposure and efficacy. In general, administer drugs at least 2 hr before or after sodium zirconium cyclosilicate.somapacitanMonitor Closely (1)ethinylestradiol will decrease the level or effect of somapacitan 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 requiredsomatrogonMonitor Closely (1)ethinylestradiol will decrease the level or effect of somatrogon 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 requiredsomatropinMonitor Closely (1)ethinylestradiol will decrease the level or effect of somatropin 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 requiredSt John's WortSerious - Use Alternative (1)St John's Wort 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.stiripentolMonitor Closely (1)stiripentol, ethinylestradiol. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.sugammadex sodiumSerious - Use Alternative (1)sugammadex sodium decreases effects of ethinylestradiol by receptor binding competition. Avoid or Use Alternate Drug. In vitro binding studies showed that sugammadex may bind to progestogen, thereby decreasing progestogen exposure. Therefore, a sugammadex bolus dose is considered to be equivalent to missing dose(s) of hormonal contraceptives containing an estrogen or progestogen. If an oral contraceptive is taken on the same day of sugammadex, or the patient has a transdermal or implant hormonal contraceptive, the patient must use an additional, nonhormonal contraceptive method or back-up method of contraception (eg, condoms and spermicides) for the next 7 days.sulfadiazineMonitor Closely (1)sulfadiazine 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.sulfamethoxazoleMonitor Closely (1)sulfamethoxazole 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.sulfisoxazoleMonitor Closely (1)sulfisoxazole 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.tacrolimusMonitor Closely (1)ethinylestradiol will increase the level or effect of tacrolimus by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.tazemetostatMonitor Closely (2)tazemetostat will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. ethinylestradiol will increase the level or effect of tazemetostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.tecovirimatMonitor Closely (1)tecovirimat will decrease the level or effect of ethinylestradiol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.teriflunomideMonitor Closely (1)teriflunomide increases levels of ethinylestradiol by unknown mechanism. Use Caution/Monitor.tetracyclineMonitor Closely (1)tetracycline 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.Serious - Use Alternative (1)ferrous fumarate decreases levels of tetracycline by inhibition of GI absorption. Applies only to oral form of both agents. Avoid or Use Alternate Drug.theophyllineMonitor Closely (1)ethinylestradiol will increase the level or effect of theophylline by affecting hepatic enzyme CYP1A2 metabolism. Use Caution/Monitor.thyroid desiccatedMonitor Closely (1)ferrous fumarate decreases levels of thyroid desiccated by inhibition of GI absorption. Applies