Zafirlukast interactions

Co-administration of such combinations of a CYP2C9 inhibitor plus a strong or moderate CYP3A inhibitor with TRACLEER is not recommended. (Bosentan label, Drug interactions)

Moderate dual CYP3A4 and CYP2C9 inhibitors (fluconazole, amiodarone) or use of combined CYP3A4 and CYP2C9 inhibitors may increase exposure to macitentan: avoid co-administration with OPSUMIT ( 7.3 , 12.3 ). (Macitentan label, Drug interactions)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

Coadministration of zafirlukast (40 mg/day) with aspirin (650 mg four times daily) resulted in mean increased plasma levels of zafirlukast by approximately 45%. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (40 mg/day) with aspirin (650 mg four times daily) resulted in mean increased plasma levels of zafirlukast by approximately 45%. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

HIV Protease inhibitor — Ritonavir (600 mg twice daily), a strong CYP3A4 inhibitor, which also inhibits CYP2C9, increased avanafil 50 mg single-dose C max and AUC equal to approximately 2-fold and 13-fold, and prolonged the half-life of avanafil to approximately 9 hours in healthy volunteers. (Avanafil label, Drug interactions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (40 mg/day) with aspirin (650 mg four times daily) resulted in mean increased plasma levels of zafirlukast by approximately 45%. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (40 mg/day) with aspirin (650 mg four times daily) resulted in mean increased plasma levels of zafirlukast by approximately 45%. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Amiodarone Amiodarone and its metabolite desethyl amiodarone, inhibitors of CYP2C9, and P- glycoprotein increased concentrations of the S(-)-enantiomer of carvedilol by at least 2 fold [see Clinical Pharmacology (12.5) ]. (Carvedilol label, Drug interactions)

Co-administration of celecoxib with drugs that are known to inhibit CYP2C9 (e.g., fluconazole) may enhance the exposure and toxicity of celecoxib whereas co-administration with CYP2C9 inducers (e.g., rifampin) may lead to compromised efficacy of celecoxib. (Celecoxib label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Co-administration of diclofenac with CYP2C9 inhibitors (e.g. voriconazole) may enhance the exposure and toxicity of diclofenac whereas co- administration with CYP2C9 inducers (e.g. rifampin) may lead to compromised efficacy of diclofenac. (Diclofenac label, Drug interactions)

Co-administration of diclofenac with CYP2C9 inhibitors (e.g., voriconazole) may enhance the exposure and toxicity of diclofenac [see Clinical Pharmacology (12.3) ] whereas co-administration with CYP2C9 inducers (e.g., rifampin) may lead to compromised efficacy of diclofenac. (Diclofenac and misoprostol label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously co-administered with dofetilide as they can potentially increase dofetilide levels. (Dofetilide label, Drug interactions)

Monitor for increased dronabinol-related adverse reactions when dronabinol oral solution is co-administered with inhibitors of CYP2C9 (e.g., amiodarone, fluconazole) and inhibitors of CYP3A4 enzymes (e.g., ketoconazole, itraconazole, clarithromycin, ritonavir, erythromycin, grapefruit juice). (Dronabinol label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Effect of TRIKAFTA on Other Drugs CYP2C9 Substrates Ivacaftor may inhibit CYP2C9; therefore, monitoring of the international normalized ratio (INR) during concomitant use of TRIKAFTA with warfarin is recommended. (Elexacaftor, tezacaftor, and ivacaftor label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

In a drug interaction study in 11 asthmatic patients, coadministration of a single dose of zafirlukast (40 mg) with erythromycin (500 mg three times daily for 5 days) to steady-state resulted in decreased mean plasma levels of zafirlukast by approximately 40% due to a decrease in zafirlukast bioavailability. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

Coadministration of zafirlukast with fluconazole, a moderate CYP2C9 inhibitor, resulted in increased plasma levels of zafirlukast, by approximately 58% (90% CI:28, 95). (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Strong CYP3A4 or CYP2C9 Inhibitors Patients with renal or hepatic impairment who are taking strong inhibitors of CYP3A4 and CYP2C9 may have a significant increase in exposure to VIMPAT. (Lacosamide label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Thus concomitant usage of CYP2C9 inhibitors (such as amiodarone, fluconazole, and sulphaphenazole) may lead to abnormally high plasma levels of meloxicam due to reduced metabolic clearance [ see Use in Specific Populations ( 8.8 ); and Clinical Pharmacology ( 12.3 , 12.5 ) ]. (Meloxicam label, Drug interactions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

…salicylates, monoamine oxidase inhibitors, non-selective beta-adrenergic-blocking agents, anabolic hormones (e.g., methandrostenolone), guanethidine, gymnema sylvestre, glucomannan, thioctic acid, and inhibitors of CYP2C9 (e.g., amiodarone, fluconazole, voriconazole, sulfinpyrazone) or in patients known to be poor metabolizers of CYP2C9 substrates, alcohol. (Nateglinide label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (40 mg/day) with aspirin (650 mg four times daily) resulted in mean increased plasma levels of zafirlukast by approximately 45%. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Fluconazole (strong CYP2C9 inhibitor): Increases systemic exposure of ramelteon; administer with caution. (Ramelteon label, Drug interactions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

Rosuvastatin plasma levels can be significantly increased with concomitant administration of inhibitors of CYP2C9 and transporters. (Rosuvastatin label, Drug interactions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Coadministration of zafirlukast (20 mg/day) or placebo at steady-state with a single dose of sustained release theophylline preparation (16 mg/kg) in 16 healthy boys and girls (6 through 11 years of age) resulted in no significant differences in the pharmacokinetic parameters of theophylline. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

CYP2C9: Concomitant use with CYP2C9 inhibitors can decrease torsemide clearance. (Torsemide label, Drug interactions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

As zafirlukast is known to be an inhibitor of CYP3A4 in vitro , it is reasonable to employ appropriate clinical monitoring when these drugs are coadministered with zafirlukast. (Zafirlukast label, Precautions)

Zafirlukast exposure is likely to be increased by other moderate and strong CYP2C9 inhibitors. (Zafirlukast label, Precautions)

Concomitant Warfarin Administration: Coadministration of zafirlukast with warfarin results in a clinically significant increase in prothrombin time (PT). (Zafirlukast label, Warnings)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

An open-label, nonrandomized clinical study examined the immune responsiveness to varicella vaccine in 243 asthma patients 12 months to 8 years of age who were treated with budesonide inhalation suspension 0.25 mg to 1 mg daily (n=151) or non-corticosteroid asthma therapy (n=92) (i.e., beta 2 -agonists, leukotriene receptor antagonists, cromones). (Budesonide label, Warnings and precautions)

An open-label, nonrandomized clinical study examined the immune responsiveness to varicella vaccine in 243 asthma patients 12 months to 8 years of age who were treated with budesonide inhalation suspension 0.25 mg to 1 mg daily (n=151) or noncorticosteroid asthma therapy (n=92) (i.e., beta 2 -agonists, leukotriene receptor antagonists, cromones). (Budesonide and formoterol label, Warnings and precautions)

No formal drug-drug interaction studies with zafirlukast and other drugs known to be metabolized by the cytochrome P450 2C9 isoenzyme (e.g., tolbutamide, phenytoin, carbamazepine) have been conducted; however, care should be exercised when zafirlukast is coadministered with these drugs . (Zafirlukast label, Precautions)

However, at high concentrations in vitro , clopidogrel inhibits CYP2C9. (Clopidogrel label, Drug interactions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

No formal drug-drug interaction studies with zafirlukast and other drugs known to be metabolized by the cytochrome P450 2C9 isoenzyme (e.g., tolbutamide, phenytoin, carbamazepine) have been conducted; however, care should be exercised when zafirlukast is coadministered with these drugs . (Zafirlukast label, Precautions)

No other formal drug-drug interaction studies between zafirlukast and marketed drugs known to be metabolized by the P450 3A4 (CYP3A4) isoenzyme (e.g., dihydropyridine calcium-channel blockers, cyclosporin, cisapride) have been conducted. (Zafirlukast label, Precautions)

Fluconazole is an inhibitor of CYP2C9 and CYP3A enzymes. (Terbinafine label, Drug interactions)

Toremifene is a weak inhibitor of CYP2C9. (Toremifene label, Drug interactions)

The interaction is a consequence of blocking hepatic metabolism of vardenafil by ritonavir, a HIV protease inhibitor and a highly strong CYP3A4 inhibitor, which also inhibits CYP2C9. (Vardenafil label, Drug interactions)

CYP2C9 Venlafaxine did not inhibit CYP2C9 in vitro . (Venlafaxine label, Drug interactions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)

In a single-blind, parallel-group, 3-week study in 39 healthy female subjects taking oral contraceptives, 40 mg twice daily of zafirlukast had no significant effect on ethinyl estradiol plasma concentrations or contraceptive efficacy. (Zafirlukast label, Precautions)