substrates initiated within 9 months after last SC dose of lenacapavir, which may increase potential risk of adverse reactions of CYP3A4 substrates. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors.levoketoconazolelevoketoconazole 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/24 lithiumlithium and vardenafil both increase QTc interval. Use Caution/Monitor.lonafarniblonafarnib will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Avoid coadministration with sensitive CYP3A substrates. If coadministration unavoidable, monitor for adverse reactions and reduce CYP3A substrate dose in accordance with product labeling. Vardenafil dose may need to be reduced if coadministered with moderate or strong CYP3A4 inhibitors. lopinavirlopinavir 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 lumefantrinelumefantrine will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.maravirocmaraviroc, vardenafil. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.methylprednisolonemethylprednisolone will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.metronidazolemetronidazole 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 mifepristonemifepristone, vardenafil. QTc interval. Modify Therapy/Monitor Closely. Use alternatives if available.mifepristone 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 mirtazapinemirtazapine and vardenafil both increase QTc interval. Use Caution/Monitor.mitotanemitotane decreases levels of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.nefazodonenefazodone 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 nelfinavirnelfinavir 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 netupitant/palonosetronnetupitant/palonosetron 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 nevirapinenevirapine will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nifedipinenifedipine will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nilotinibnilotinib will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nirmatrelvir/ritonavirnirmatrelvir/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 hrnitroprusside sodiumnitroprusside sodium, vardenafil. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects.olanzapineolanzapine and vardenafil both increase QTc interval. Use Caution/Monitor.olodaterol inhaledvardenafil and olodaterol inhaled both increase QTc interval. Use Caution/Monitor. Drugs that prolong the QTc interval and may potentiate the effects of beta2 agonists on the cardiovascular system; increased risk of ventricular arrhythmiasosilodrostatosilodrostat and vardenafil both increase QTc interval. Use Caution/Monitor.osimertinibosimertinib and vardenafil both increase QTc interval. Use Caution/Monitor. Conduct periodic monitoring with ECGs and electrolytes in patients taking drugs known to prolong the QTc interval.oxcarbazepineoxcarbazepine will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ozanimodozanimod and vardenafil both increase QTc interval. Modify Therapy/Monitor Closely. The potential additive effects on heart rate, treatment with ozanimod should generally not be initiated in patients who are concurrently treated with QT prolonging drugs with known arrhythmogenic properties.pasireotidevardenafil and pasireotide both increase QTc interval. Modify Therapy/Monitor Closely.pentobarbitalpentobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.phenobarbitalphenobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.phenytoinphenytoin will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.posaconazoleposaconazole 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 prednisoneprednisone will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.primaquineprimaquine and vardenafil both increase QTc interval. Use Caution/Monitor.primidoneprimidone will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.quetiapinequetiapine, 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.quininevardenafil and quinine both increase QTc interval. Use Caution/Monitor.quinupristin/dalfopristinquinupristin/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 ribociclibribociclib 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 rifapentinerifapentine will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.ritonavirritonavir 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 hrrucaparibrucaparib 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.rufinamiderufinamide will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.saquinavirsaquinavir increases levels of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Limit vardenafil dose to 2.5 mg/24 hr.secobarbitalsecobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.selpercatinibselpercatinib increases toxicity of vardenafil by QTc interval. Use Caution/Monitor.sertralinesertraline 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 sodium sulfate/?magnesium sulfate/potassium chloridesodium 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 sulfatesodium 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. .solifenacinsolifenacin and vardenafil both increase QTc interval. Use Caution/Monitor.sorafenibsorafenib and vardenafil both increase QTc interval. Use Caution/Monitor.stiripentolstiripentol, 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.sunitinibsunitinib and vardenafil both increase QTc interval. Use Caution/Monitor.tacrolimustacrolimus and vardenafil both increase QTc interval. Use Caution/Monitor.tadalafilvardenafil, tadalafil. Other (see comment). Use Caution/Monitor. Comment: Avoid combination; duplicate therapy is not recommended.tamsulosinvardenafil, tamsulosin. Either increases effects of the other by additive vasodilation. Use Caution/Monitor. Risk of hypotension.tazemetostattazemetostat will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.tecovirimattecovirimat 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.tetracyclinetetracycline 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 inhaledtobramycin inhaled and vardenafil both increase nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Avoid concurrent or sequential use to decrease risk for ototoxicitytopiramatetopiramate will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.valbenazinevalbenazine and vardenafil both increase QTc interval. Use Caution/Monitor.verapamilverapamil 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 voclosporinvoclosporin, vardenafil. Either increases effects of the other by QTc interval. Use Caution/Monitor.voriconazolevoriconazole 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 vorinostatvorinostat and vardenafil both increase QTc interval. Use Caution/Monitor.zafirlukastzafirlukast will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (8)acetazolamideacetazolamide will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.anastrozoleanastrozole will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.azithromycinazithromycin increases toxicity of vardenafil by QTc interval. Minor/Significance Unknown.carvedilolvardenafil increases effects of carvedilol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.chloroquinechloroquine increases toxicity of vardenafil by QTc interval. Minor/Significance Unknown.cyclophosphamidecyclophosphamide will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.labetalolvardenafil increases effects of labetalol by pharmacodynamic synergism. Minor/Significance Unknown. Risk of hypotension.sapropterinsapropterin, vardenafil. Either increases effects of the other by pharmacodynamic synergism. Minor/Significance Unknown. Possible additive vasorelaxation, leading to low blood pressure.acetazolamideMinor (1)acetazolamide will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.adagrasibMonitor Closely (1)adagrasib 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)adagrasib, vardenafil. Either increases effects of the other by QTc interval. Avoid or Use Alternate Drug. Each drug prolongs the QTc interval, which may increased the risk of Torsade de pointes, other serious arryhthmias, and sudden death. If coadministration unavoidable, more frequent monitoring is recommended for such patients.albuterolMonitor Closely (1)albuterol and vardenafil both increase QTc interval. Use Caution/Monitor.alfuzosinMonitor Closely (2)vardenafil and alfuzosin both increase QTc interval. Use Caution/Monitor. alfuzosin and vardenafil both increase QTc interval. Use Caution/Monitor.Serious - Use Alternative (1)vardenafil increases effects of alfuzosin by pharmacodynamic synergism. Contraindicated. Risk of hypotension.amifostineMonitor Closely (1)amifostine, vardenafil. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Monitor blood pressure response to phosphodiesterase type 5 (PDE5) inhibitors in patients receiving concurrent blood pressure lowering therapy.amiodaroneMonitor Closely (1)amiodarone 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 amisulprideSerious - Use Alternative (1)amisulpride and vardenafil both increase QTc interval. Avoid or Use Alternate Drug. ECG monitoring is recommended if coadministered.amobarbitalMonitor Closely (1)amobarbital will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.amyl nitriteSerious - Use Alternative (1)amyl nitrite, vardenafil. Mechanism: additive vasodilation. Avoid or Use Alternate Drug. Potentially fatal hypotension.anagrelideSerious - Use Alternative (1)anagrelide and vardenafil both increase QTc interval. Avoid or Use Alternate Drug.anastrozoleMinor (1)anastrozole will increase the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.apalutamideSerious - Use Alternative (1)apalutamide will decrease the level or effect of vardenafil 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.apomorphineMonitor Closely (1)apomorphine and vardenafil both increase QTc interval. Use Caution/Monitor.aprepitantMonitor Closely (1)aprepitant 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 arformoterolMonitor Closely (1)arformoterol and vardenafil both increase QTc interval. Use Caution/Monitor.aripiprazoleMonitor Closely (1)aripiprazole and vardenafil both increase QTc interval. Use Caution/Monitor.armodafinilMonitor Closely (1)armodafinil will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.artemetherSerious - Use Alternative (1)artemether and vardenafil both increase QTc interval. Avoid or Use Alternate Drug.artemether/lumefantrineMonitor Closely (1)artemether/lumefantrine will decrease the level or effect of vardenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.asenapineMonitor Closely (1)vardenafil increases effects of asenapine by pharmacodynamic synergism. Modify