hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.quetiapineMonitor Closely (1)quetiapine, vardenafil. Either increases toxicity of the other by QTc interval. Use Caution/Monitor. Avoid use with drugs that prolong QT and in patients with risk factors for prolonged QT interval. Postmarketing cases show QT prolongation with overdose in patients with concomitant illness or with drugs known to cause electrolyte imbalance or prolong QT.quinineMonitor Closely (1)vardenafil and quinine both increase QTc interval. Use Caution/Monitor.quinupristin/dalfopristinMonitor Closely (1)quinupristin/dalfopristin will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors ribociclibMonitor Closely (1)ribociclib will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors Serious - Use Alternative (1)ribociclib increases toxicity of vardenafil by QTc interval. Avoid or Use Alternate Drug.rifabutinSerious - Use Alternative (1)rifabutin will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.rifampinSerious - Use Alternative (1)rifampin will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.rifapentineMonitor Closely (1)rifapentine will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.riociguatContraindicated (1)vardenafil, riociguat. Either increases effects of the other by additive vasodilation. Contraindicated. Coadministration of PDE-5 inhibitors (eg, avanafil, sildenafil, tadalafil, vardenafil) and guanylate cyclase stimulators (eg, riociguat) is contraindicated due to risk of additive hypotension.ritonavirMonitor Closely (1)ritonavir will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Limit vardenafil dose to 2.5 mg/72 hrrucaparibMonitor Closely (1)rucaparib will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.rufinamideMonitor Closely (1)rufinamide will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.sapropterinMinor (1)sapropterin, vardenafil. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Possible additive vasorelaxation, leading to low blood pressure.saquinavirMonitor Closely (1)saquinavir increases levels of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Limit vardenafil dose to 2.5 mg/24 hr.secobarbitalMonitor Closely (1)secobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.selpercatinibMonitor Closely (1)selpercatinib increases toxicity of vardenafil by QTc interval. Use Caution/Monitor.sertralineMonitor Closely (2)sertraline and vardenafil both increase QTc interval. Use Caution/Monitor. sertraline will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors sevofluraneSerious - Use Alternative (1)sevoflurane and vardenafil both increase QTc interval. Avoid or Use Alternate Drug.silodosinSerious - Use Alternative (1)vardenafil increases effects of silodosin by pharmacodynamic synergism. Contraindicated. Risk of hypotension.siponimodSerious - Use Alternative (1)siponimod and vardenafil both increase QTc interval. Avoid or Use Alternate Drug.sodium sulfate/?magnesium sulfate/potassium chlorideMonitor Closely (1)sodium sulfate/?magnesium sulfate/potassium chloride increases toxicity of vardenafil by QTc interval. Use Caution/Monitor. Consider predose and post-colonoscopy ECGs in patients at increased risk of serious cardiac arrhythmias. .sodium sulfate/potassium sulfate/magnesium sulfateMonitor Closely (1)sodium sulfate/potassium sulfate/magnesium sulfate increases toxicity of vardenafil by QTc interval. Use Caution/Monitor. Consider predose and post-colonoscopy ECGs in patients at increased risk of serious cardiac arrhythmias. .solifenacinMonitor Closely (1)solifenacin and vardenafil both increase QTc interval. Use Caution/Monitor.sorafenibMonitor Closely (1)sorafenib and vardenafil both increase QTc interval. Use Caution/Monitor.St John's WortSerious - Use Alternative (1)St John's Wort will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.stiripentolMonitor Closely (1)stiripentol, vardenafil. 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.sunitinibMonitor Closely (1)sunitinib and vardenafil both increase QTc interval. Use Caution/Monitor.tacrolimusMonitor Closely (1)tacrolimus and vardenafil both increase QTc interval. Use Caution/Monitor.tadalafilMonitor Closely (1)vardenafil, tadalafil. Other (see comment). Use Caution/Monitor. Comment: Avoid combination; duplicate therapy is not recommended.tamsulosinMonitor Closely (1)vardenafil, tamsulosin. Either increases effects of the other by additive vasodilation. Use Caution/Monitor. Risk of hypotension.tazemetostatMonitor Closely (1)tazemetostat will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.tecovirimatMonitor Closely (1)tecovirimat will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.terazosinSerious - Use Alternative (1)vardenafil increases effects of terazosin by pharmacodynamic synergism. Contraindicated. Risk of hypotension.tetrabenazineSerious - Use Alternative (1)tetrabenazine and vardenafil both increase QTc interval. Avoid or Use Alternate Drug.tetracyclineMonitor Closely (1)tetracycline will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors tobramycin inhaledMonitor Closely (1)tobramycin inhaled and vardenafil both increase nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Avoid concurrent or sequential use to decrease risk for ototoxicitytopiramateMonitor Closely (1)topiramate will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.tucatinibSerious - Use Alternative (1)tucatinib will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.umeclidinium bromide/vilanterol inhaledSerious - Use Alternative (1)vardenafil increases toxicity of umeclidinium bromide/vilanterol inhaled by QTc interval. Avoid or Use Alternate Drug. Exercise extreme caution when vilanterol coadministered with drugs that prolong QTc interval; adrenergic agonist effects on the cardiovascular system may be potentiated.valbenazineMonitor Closely (1)valbenazine and vardenafil both increase QTc interval. Use Caution/Monitor.vemurafenibSerious - Use Alternative (1)vemurafenib and vardenafil both increase QTc interval. Avoid or Use Alternate Drug. Concomitant use of vemurafenib with drugs that prolong QT interval is not recommended.verapamilMonitor Closely (1)verapamil will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors vericiguatContraindicated (1)vardenafil, vericiguat. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Coadministration of vericiguat with PDE-5 inhibitors may result in additive hypotensive effects.vilanterol/fluticasone furoate inhaledSerious - Use Alternative (1)vardenafil increases toxicity of vilanterol/fluticasone furoate inhaled by QTc interval. Avoid or Use Alternate Drug. Exercise extreme caution when vilanterol coadministered with drugs that prolong QTc interval; adrenergic agonist effects on the cardiovascular system may be potentiated.voclosporinMonitor Closely (1)voclosporin, vardenafil. Either increases effects of the other by QTc interval. Use Caution/Monitor.voriconazoleMonitor Closely (1)voriconazole will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors vorinostatMonitor Closely (1)vorinostat and vardenafil both increase QTc interval. Use Caution/Monitor.voxelotorSerious - Use Alternative (1)voxelotor will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.zafirlukastMonitor Closely (1)zafirlukast will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.zotepineSerious - Use Alternative (1)vardenafil increases effects of zotepine by pharmacodynamic synergism. Contraindicated. Risk of hypotension. >10% Headache (15%) Flushing (11%) 1-10% Rhinitis (9%) Dyspepsia (4%) Flulike syndrome (3%) Sinusitis (3%) Back pain (2%) Dizziness (2%) Increased creatine phosphokinase (2%) Nausea (2%) <1% Anaphylaxis Angina Insomnia Myocardial infarction (MI) Postural hypotension Priapism Pruritus Rash Contraindications Hypersensitivity Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension Coadministration with nitrates Coadministration with nitrates (either regularly and/or intermittently) and nitric oxide donors Consistent with the effects of PDE5 inhibition on the nitric oxide/cyclic guanosine monophosphate pathway, PDE5 inhibitors may potentiate the hypotensive effects of nitrates A suitable time interval following PDE5 dosing for the safe administration of nitrates or nitric oxide donors has not been determined Cautions Use with caution in anatomical deformation of the penis (such as angulation, cavernosal fibrosis, or Peyronie’s disease), cardiovascular disease, left ventricular outflow obstruction, bleeding disorders, active peptic ulcer disease, liver disease, renal impairment, multidrug antihypertensive regimens, retinitis pigmentosa, concomitant use of CYP3A4 inhibitors, patients who have conditions that may predispose them to priapism (such as sickle cell anemia, multiple myeloma, or leukemia) There have been rare reports of prolonged erections >4 hours and priapism (painful erections greater than 6 hours in duration) for this class of compounds, including vardenafil; in the event that an erection persists >4 hours, the patient should seek immediate medical assistance; if priapism is not treated immediately, penile tissue damage and permanent loss of potency may result Physicians should consider the cardiovascular status of their patients; there is a degree of cardiac risk associated with sexual activity; treatment for erectile dysfunction, should not be used in men for whom sexual activity is not recommended because of their underlying cardiovascular status Patients with left ventricular outflow obstruction, (for example, aortic stenosis and idiopathic hypertrophic subaortic stenosis) can be sensitive to the action of vasodilators including PDE5 inhibitors Until further information available, use is not recommended in unstable angina; hypotension (resting systolic blood pressure of <90 mmHg); uncontrolled hypertension (>170/110 mmHg); recent history of stroke, life-threatening arrhythmia, or myocardial infarction (within last 6 months); severe cardiac failure Consider counseling patients about protective measures necessary to guard against sexually transmitted diseases, including Human Immunodeficiency Virus (HIV); drug offers no protection against sexually transmitted diseases Patients taking Class 1A (eg, quinidine, procainamide) or Class III (eg, amiodarone, sotalol) antiarrhythmic medications or those with congenital QT prolongation, should avoid using drug Safety and efficacy of drug used in combination with other treatments for erectile dysfunction not studied; use of such combinations not recommended Not to be taken with other phosphodiesterase (PDE)-5 inhibitors (eg, sildenafil, tadalafil) Vision loss may occur rarely and may be a sign of non-arteritic anterior ischemic optic neuropathy (NAION); patient should seek medical assistance for sudden loss in one or both eyes; patients who have already experienced NAION are at increased risk of recurrence; use is not recommended in patients with known degenerative retinal disorders May increase risk of rare sudden vision loss attributed to nonarteritic ischemic optic neuropathy; if vision problems arise, discontinue, and contact physician The drug has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 7 mmHg systolic and 8 mmHg diastolic); while this normally would be expected to be of little consequence in most patients, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects Physicians should advise patients to stop taking all PDE5 inhibitors, and seek prompt medical attention in event of sudden decrease or loss of hearing; these events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to intake of PDE5 inhibitors, including vardenafil; it is not possible to determine whether these events are related directly to use of PDE5 inhibitors or to other factors Alpha blocekrs (H4) Caution advised when PDE5 inhibitors co-administered with alpha-blockers; PDE5 inhibitors, and alpha-adrenergic blocking agents are both vasodilators with blood-pressure lowering effects; when vasodilators are used in combination, an additive effect on blood pressure may be anticipated; in some patients, concomitant use of these two drug classes can lower blood pressure significantly leading to symptomatic hypotension (eg, fainting) Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor; patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors In patients who are stable on alpha-blocker therapy, initiate PDE5 inhibitors at lowest recommended starting dose In patients already taking optimized dose of PDE5 inhibitor, initiate alpha-blocker therapy at lowest dose; stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure in patients taking a PDE5 inhibitor Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs Drug interaction overview(H4) Concomitant administration with potent CYP3A4 inhibitors (such as ritonavir, indinavir, cobicistat, ketoconazole) or moderate CYP3A4 inhibitors (such as erythromycin) increases plasma concentrations of drug;