Viagra ( Sildenafil )

tadalafil (Rx)

PRN use: 10 mg PO initially before sexual activity, with or without food; may be increased to 20 mg or reduced to 5 mg on basis of efficacy and tolerability; in most patients, maximum dosing frequency is once daily

Once-daily use: 2.5 mg/day PO in single daily dose, without regard to timing of sexual activity, with or without food; may be increased to 5 mg/day on basis of efficacy and tolerability

Dosing considerations

  • PRN use: Decrease dose with concomitant use of potent CYP3A4 inhibitor (eg, ritonavir, ketoconazole, itraconazole); not to exceed 10 mg/72 hr
  • Once-daily use: Decrease dose with concomitant use of potent CYP3A4 inhibitor (eg, ritonavir, ketoconazole, itraconazole); not to exceed 2.5 mg/day

Benign Prostatic Hyperplasia

Indicated for treatment of signs and symptoms of benign prostatic hyperplasia (BPH); daily use also indicated for treatment of patients with both BPH and erectile dysfunction

Cialis or generic equivalent only

BPH: 5 mg PO once daily

BPH with ED: 5 mg PO once daily, taken at approximately same time each day without regard to timing of sexual activity

Coadministration with finasteride for BPH: Tadalafil 5 mg plus finasteride 5 mg PO once daily for ≤26 weeks; incremental benefit of tadalafil decreases from 4 weeks until 26 weeks, and the benefit beyond 26 weeks is unknown

Pulmonary Arterial Hypertension

Indicated for pulmonary arterial hypertension (PAH) (WHO Group 1) to improve exercise ability; studies establishing effectiveness included predominately patients with NYHA Functional Class II – III symptoms and etiologies of idiopathic or heritable PAH (61%) or PAH associated with connective tissue diseases (23%)

Adcirca, Alyq, or generic equivalent only

40 mg PO once daily; dividing dose for more frequent dosing is not recommended

Patients also taking ritonavir: 20 mg PO once daily initially for ≥1 week; may be increased to 40 mg/day on basis of tolerability

Dosing considerations

  • If possible, avoid coadministration with CYP3A4 inhibitors; if coadministration is essential, long-term therapy is indicated, or strong CYP3A4 inhibitors are required, modify or hold dose
  • Patients already taking strong CYP3A4 inhibitor who require tadalafil: 20 mg PO once daily; may be increased to 40 mg/day on basis of tolerability
  • Patients already taking tadalafil who require strong CYP3A4 inhibitor: Avoid using tadalafil while starting strong CYP3A4 inhibitor; stop tadalafil ≥24 hours before starting strong CYP3A4 inhibitor; after 1 week, resume tadalafil at 20 mg PO once daily; may be increased to 40 mg/day on basis of tolerability

Dosing Modifications

Renal impairment (ED)

Cialis (PRN use)
  • Mild (CrCl ≥51 mL/min): No dosage adjustment needed
  • Moderate (CrCl 30-50 mL/min): Not to exceed 5 mg PO once daily initially; maximum dosage, 10 mg PO q48hr
  • Severe (CrCl Enter a drug name and tadalafil

Contraindicated

Serious – Use Alternative

Significant – Monitor Closely

Minor

Contraindicated (11)

isosorbide dinitrate, tadalafil. Mechanism: additive vasodilation. Contraindicated. Contraindicated. Potentially fatal hypotension. Allow 48h after last tadalafil dose before nitrate administration.

isosorbide mononitrate, tadalafil. Mechanism: additive vasodilation. Contraindicated. Contraindicated. Potentially fatal hypotension. Allow 48h after last tadalafil dose before nitrate administration.

nitroglycerin IV, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

nitroglycerin PO, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

tadalafil increases effects of nitroglycerin rectal by additive vasodilation. Contraindicated. Use of nitroglycerin within a few days of PDE5 inhibitors is contraindicated. PDE5 inhibitors have been shown to potentiate the hypotensive effects of organic nitrates.

nitroglycerin sublingual, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

nitroglycerin topical, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

nitroglycerin transdermal, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

nitroglycerin translingual, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

tadalafil, 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; do not administer 24 hr before or within 48hr of each other.

tadalafil, vericiguat. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Coadministration of vericiguat with PDE-5 inhibitors may result in additive hypotensive effects.

Serious – Use Alternative (27)

abametapir will increase the level or effect of tadalafil 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.

amyl nitrite, tadalafil. Mechanism: additive vasodilation. Avoid or Use Alternate Drug. Contraindicated. Potentially fatal hypotension. Allow 48h after last tadalafil dose before nitrate administration.

apalutamide will decrease the level or effect of tadalafil 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.

atazanavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

clarithromycin will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

cobicistat will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Adjust tadalafil dose for PAH; if on cobicistat, start tadalafil 20 mg/day and may increase up to 40 mg/day; avoid tadalafil when starting cobicistat; for ED, may take a single dose of tadalafil not exceeding 10 mg in 72 hr.

darunavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Adjust tadalafil dose for PAH; if on cobicistat, start tadalafil 20 mg/day and may increase up to 40 mg/day; avoid tadalafil when starting cobicistat; for ED, may take a single dose of tadalafil not exceeding 10 mg in 72 hr.

enzalutamide will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

erythromycin base will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

erythromycin ethylsuccinate will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

erythromycin lactobionate will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

erythromycin stearate will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

fexinidazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

fosamprenavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

idelalisib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates

indinavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

itraconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

ketoconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

levoketoconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

lonafarnib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with sensitive CYP3A substrates. If coadministration unavoidable, monitor for adverse reactions and reduce CYP3A substrate dose in accordance with product labeling.

lopinavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

nelfinavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

nicardipine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

nirmatrelvir/ritonavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration if tadalafil used for pulmonary arterial hpertension. Reduce tadalafil dose if used for erectile dysfunction.

ritonavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

tucatinib will increase the level or effect of tadalafil 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.

voxelotor will increase the level or effect of tadalafil 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.

Monitor Closely (154)

tadalafil increases effects of acebutolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of acetazolamide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of alfuzosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of aliskiren by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

amifostine, tadalafil. 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.

tadalafil increases effects of amiloride by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

amiodarone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

tadalafil increases effects of amlodipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

amobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

aprepitant will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

armodafinil will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

artemether/lumefantrine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of asenapine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

atazanavir increases levels of tadalafil by decreasing metabolism. Use Caution/Monitor. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

tadalafil increases effects of atenolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of azilsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of benazepril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of betaxolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

bicalutamide will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

tadalafil increases effects of bisoprolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

bosentan will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

budesonide will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of bumetanide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

butabarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

butalbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of candesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of captopril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

carbamazepine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

tadalafil increases effects of carvedilol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

cenobamate will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.

tadalafil increases effects of chlorthalidone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

cimetidine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of clevidipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of clonidine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

clotrimazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

conivaptan will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

crizotinib increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dose reduction may be needed for coadministered drugs that are predominantly metabolized by CYP3A.

crofelemer increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Crofelemer has the potential to inhibit CYP3A4 at concentrations expected in the gut; unlikely to inhibit systemically because minimally absorbed.

cyclosporine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

dabrafenib will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.

dasatinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

deferasirox will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

desipramine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

dexamethasone will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

diltiazem will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

dronedarone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

duvelisib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with duvelisib increases AUC of a sensitive CYP3A4 substrate which may increase the risk of toxicities of these drugs. Consider reducing the dose of the sensitive CYP3A4 substrate and monitor for signs of toxicities of the coadministered sensitive CYP3A substrate.

efavirenz will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

elagolix decreases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust tadalafil dose for PAH; if on Stribild, start tadalafil 20 mg/day; avoid tadalafil when starting Stribild; for ED, a single dose of tadalafil not exceeding 10 mg in 72 hr.

tadalafil increases effects of enalapril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

encorafenib, tadalafil. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

tadalafil increases effects of eplerenone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of eprosartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

eslicarbazepine acetate will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

tadalafil increases effects of esmolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of ethacrynic acid by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

ethanol, tadalafil. Either increases effects of the other by additive vasodilation. Use Caution/Monitor. Combination may increase risk of orthostatic hypotension, tachycardia, dizziness and headache.

etravirine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

fedratinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.

tadalafil increases effects of felodipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

fluconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

fluvoxamine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of fosinopril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

fosphenytoin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

tadalafil increases effects of furosemide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

grapefruit will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

griseofulvin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of guanfacine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

haloperidol will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

tadalafil increases effects of hydralazine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

iloperidone increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4.

imatinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

tadalafil increases effects of indapamide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

isoniazid will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

tadalafil increases effects of isradipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

istradefylline will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

tadalafil increases effects of labetalol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

lapatinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

letermovir increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of lisinopril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of losartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

lumefantrine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

maraviroc, tadalafil. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.

marijuana will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of metolazone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of metoprolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

metronidazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

mifepristone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of minoxidil by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

mitotane decreases levels of tadalafil 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.

tadalafil increases effects of nadolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

nafcillin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of nebivolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

nefazodone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

nevirapine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

nifedipine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of nifedipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

nilotinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of nimodipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of nisoldipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

nitroprusside sodium, tadalafil. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects.

tadalafil increases effects of olmesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

oxcarbazepine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

pazopanib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of penbutolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

pentobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

phenobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

tadalafil increases effects of phenoxybenzamine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of phentolamine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

phenytoin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

posaconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of prazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

primidone will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

tadalafil increases effects of propranolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of quinapril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

quinupristin/dalfopristin will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of ramipril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

ribociclib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

rifabutin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

rifampin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

rifapentine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

rucaparib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.

rufinamide will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of sacubitril/valsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

sapropterin, tadalafil. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Possible additive vasorelaxation, leading to low blood pressure.

saquinavir increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Potential for increased toxicity. .

secobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

sertraline will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

tadalafil increases effects of silodosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of sotalol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of spironolactone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

St John’s Wort will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

stiripentol, tadalafil. 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.

tadalafil, tamsulosin. Either increases effects of the other by additive vasodilation. Use Caution/Monitor. Risk of hypotension.

tazemetostat will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tecovirimat will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.

tadalafil increases effects of telmisartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of terazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tetracycline will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

tadalafil increases effects of timolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tipranavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

tobramycin inhaled and tadalafil both increase nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Avoid concurrent or sequential use to decrease risk for ototoxicity

topiramate will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

tadalafil increases effects of torsemide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of trandolapril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of triamterene by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of valsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

vardenafil, tadalafil. Other (see comment). Use Caution/Monitor. Comment: Avoid combination; duplicate therapy is not recommended.

verapamil will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.

voriconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

zafirlukast will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Minor (1)

ranolazine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Ranolazine may theoretically increase plasma concentrations of CYP3A4 substrates, such as tadalafil.

Serious – Use Alternative (1) abametapir will increase the level or effect of tadalafil 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.

Monitor Closely (1) tadalafil increases effects of acebutolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of acetazolamide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of alfuzosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of aliskiren by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) amifostine, tadalafil. 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.

Monitor Closely (1) tadalafil increases effects of amiloride by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) amiodarone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Monitor Closely (1) tadalafil increases effects of amlodipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) amobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Serious – Use Alternative (1) amyl nitrite, tadalafil. Mechanism: additive vasodilation. Avoid or Use Alternate Drug. Contraindicated. Potentially fatal hypotension. Allow 48h after last tadalafil dose before nitrate administration.

Serious – Use Alternative (1) apalutamide will decrease the level or effect of tadalafil 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.

Monitor Closely (1) aprepitant will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) armodafinil will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) artemether/lumefantrine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of asenapine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) atazanavir increases levels of tadalafil by decreasing metabolism. Use Caution/Monitor. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability. Serious – Use Alternative (1) atazanavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

Monitor Closely (1) tadalafil increases effects of atenolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of azilsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of benazepril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of betaxolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) bicalutamide will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Monitor Closely (1) tadalafil increases effects of bisoprolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) bosentan will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) budesonide will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of bumetanide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) butabarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) butalbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of candesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of captopril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) carbamazepine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) tadalafil increases effects of carvedilol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) cenobamate will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Increase dose of CYP3A4 substrate, as needed, when coadministered with cenobamate.

Monitor Closely (1) tadalafil increases effects of chlorthalidone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) cimetidine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Serious – Use Alternative (1) clarithromycin will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Monitor Closely (1) tadalafil increases effects of clevidipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of clonidine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) clotrimazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Serious – Use Alternative (1) cobicistat will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Adjust tadalafil dose for PAH; if on cobicistat, start tadalafil 20 mg/day and may increase up to 40 mg/day; avoid tadalafil when starting cobicistat; for ED, may take a single dose of tadalafil not exceeding 10 mg in 72 hr.

Monitor Closely (1) conivaptan will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Monitor Closely (1) crizotinib increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Dose reduction may be needed for coadministered drugs that are predominantly metabolized by CYP3A.

Monitor Closely (1) crofelemer increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Crofelemer has the potential to inhibit CYP3A4 at concentrations expected in the gut; unlikely to inhibit systemically because minimally absorbed.

Monitor Closely (1) cyclosporine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) dabrafenib will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely.

Serious – Use Alternative (1) darunavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Adjust tadalafil dose for PAH; if on cobicistat, start tadalafil 20 mg/day and may increase up to 40 mg/day; avoid tadalafil when starting cobicistat; for ED, may take a single dose of tadalafil not exceeding 10 mg in 72 hr.

Monitor Closely (1) dasatinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) deferasirox will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) desipramine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Monitor Closely (1) dexamethasone will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) diltiazem will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of doxazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) dronedarone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) duvelisib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Coadministration with duvelisib increases AUC of a sensitive CYP3A4 substrate which may increase the risk of toxicities of these drugs. Consider reducing the dose of the sensitive CYP3A4 substrate and monitor for signs of toxicities of the coadministered sensitive CYP3A substrate.

Monitor Closely (1) efavirenz will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) elagolix decreases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Elagolix is a weak-to-moderate CYP3A4 inducer. Monitor CYP3A substrates if coadministered. Consider increasing CYP3A substrate dose if needed.

Monitor Closely (1) elvitegravir/cobicistat/emtricitabine/tenofovir DF increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust tadalafil dose for PAH; if on Stribild, start tadalafil 20 mg/day; avoid tadalafil when starting Stribild; for ED, a single dose of tadalafil not exceeding 10 mg in 72 hr.

Monitor Closely (1) tadalafil increases effects of enalapril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) encorafenib, tadalafil. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Encorafenib both inhibits and induces CYP3A4 at clinically relevant plasma concentrations. Coadministration of encorafenib with sensitive CYP3A4 substrates may result in increased toxicity or decreased efficacy of these agents.

Serious – Use Alternative (1) enzalutamide will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug.

Monitor Closely (1) tadalafil increases effects of eplerenone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of eprosartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) erythromycin base will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Serious – Use Alternative (1) erythromycin ethylsuccinate will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Serious – Use Alternative (1) erythromycin lactobionate will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Serious – Use Alternative (1) erythromycin stearate will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Monitor Closely (1) eslicarbazepine acetate will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) tadalafil increases effects of esmolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of ethacrynic acid by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) ethanol, tadalafil. Either increases effects of the other by additive vasodilation. Use Caution/Monitor. Combination may increase risk of orthostatic hypotension, tachycardia, dizziness and headache.

Monitor Closely (1) etravirine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) fedratinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Adjust dose of drugs that are CYP3A4 substrates as necessary.

Monitor Closely (1) tadalafil increases effects of felodipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) fexinidazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Fexinidazole inhibits CYP3A4. Coadministration may increase risk for adverse effects of CYP3A4 substrates.

Monitor Closely (1) fluconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) fluvoxamine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Serious – Use Alternative (1) fosamprenavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

Monitor Closely (1) tadalafil increases effects of fosinopril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) fosphenytoin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) tadalafil increases effects of furosemide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) grapefruit will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) griseofulvin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of guanfacine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) haloperidol will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Monitor Closely (1) tadalafil increases effects of hydralazine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of hydrochlorothiazide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) idelalisib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Idelalisib is a strong CYP3A inhibitor; avoid coadministration with sensitive CYP3A substrates

Monitor Closely (1) iloperidone increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Iloperidone is a time-dependent CYP3A inhibitor and may lead to increased plasma levels of drugs predominantly eliminated by CYP3A4.

Monitor Closely (1) imatinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Monitor Closely (1) tadalafil increases effects of indapamide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) indinavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

Monitor Closely (1) tadalafil increases effects of irbesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) isoniazid will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Contraindicated (1) isosorbide dinitrate, tadalafil. Mechanism: additive vasodilation. Contraindicated. Contraindicated. Potentially fatal hypotension. Allow 48h after last tadalafil dose before nitrate administration.

Contraindicated (1) isosorbide mononitrate, tadalafil. Mechanism: additive vasodilation. Contraindicated. Contraindicated. Potentially fatal hypotension. Allow 48h after last tadalafil dose before nitrate administration.

Monitor Closely (1) tadalafil increases effects of isradipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) istradefylline will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Istradefylline 40 mg/day increased peak levels and AUC of CYP3A4 substrates in clinical trials. This effect was not observed with istradefylline 20 mg/day. Consider dose reduction of sensitive CYP3A4 substrates.

Serious – Use Alternative (1) itraconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Serious – Use Alternative (1) ketoconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

Monitor Closely (1) tadalafil increases effects of labetalol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) lapatinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) letermovir increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Serious – Use Alternative (1) levoketoconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

Monitor Closely (1) tadalafil increases effects of lisinopril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) lonafarnib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration with sensitive CYP3A substrates. If coadministration unavoidable, monitor for adverse reactions and reduce CYP3A substrate dose in accordance with product labeling.

Serious – Use Alternative (1) lopinavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

Monitor Closely (1) tadalafil increases effects of losartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) lumefantrine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) maraviroc, tadalafil. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Increased risk of orthostatic hypotension.

Monitor Closely (1) marijuana will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of metolazone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of metoprolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) metronidazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) mifepristone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of minoxidil by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) mitotane decreases levels of tadalafil 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.

Monitor Closely (1) tadalafil increases effects of nadolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) nafcillin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of nebivolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) nefazodone will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Serious – Use Alternative (1) nelfinavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

Monitor Closely (1) nevirapine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Serious – Use Alternative (1) nicardipine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; significantly increased levels may result in significant adverse events including severe hypotension, syncope, visual changes, and priapism.

Monitor Closely (2) nifedipine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.

tadalafil increases effects of nifedipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) nilotinib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of nimodipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) nirmatrelvir/ritonavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid coadministration if tadalafil used for pulmonary arterial hpertension. Reduce tadalafil dose if used for erectile dysfunction.

Monitor Closely (1) tadalafil increases effects of nisoldipine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Contraindicated (1) nitroglycerin IV, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

Contraindicated (1) nitroglycerin PO, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

Contraindicated (1) tadalafil increases effects of nitroglycerin rectal by additive vasodilation. Contraindicated. Use of nitroglycerin within a few days of PDE5 inhibitors is contraindicated. PDE5 inhibitors have been shown to potentiate the hypotensive effects of organic nitrates.

Contraindicated (1) nitroglycerin sublingual, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

Contraindicated (1) nitroglycerin topical, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

Contraindicated (1) nitroglycerin transdermal, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

Contraindicated (1) nitroglycerin translingual, tadalafil. Mechanism: additive vasodilation. Contraindicated. Potentially fatal hypotension.

Monitor Closely (1) nitroprusside sodium, tadalafil. Mechanism: pharmacodynamic synergism. Use Caution/Monitor. Additive hypotensive effects.

Monitor Closely (1) tadalafil increases effects of olmesartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) oxcarbazepine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) pazopanib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of penbutolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) pentobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) phenobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) tadalafil increases effects of phenoxybenzamine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of phentolamine by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) phenytoin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) posaconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of prazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) primidone will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) tadalafil increases effects of propranolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of quinapril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) quinupristin/dalfopristin will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of ramipril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Minor (1) ranolazine will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Ranolazine may theoretically increase plasma concentrations of CYP3A4 substrates, such as tadalafil.

Monitor Closely (1) ribociclib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) rifabutin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) rifampin will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) rifapentine will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Contraindicated (1) tadalafil, 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; do not administer 24 hr before or within 48hr of each other.

Serious – Use Alternative (1) ritonavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Stop tadalafil >24 hours prior to protease inhibitor (PI) initiation, restart 7 days after PI initiation at 20 mg once daily, and increase to 40 mg once daily based on tolerability.

Monitor Closely (1) rucaparib will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.

Monitor Closely (1) rufinamide will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of sacubitril/valsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) sapropterin, tadalafil. Either increases effects of the other by pharmacodynamic synergism. Use Caution/Monitor. Possible additive vasorelaxation, leading to low blood pressure.

Monitor Closely (1) saquinavir increases levels of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Potential for increased toxicity. .

Monitor Closely (1) secobarbital will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) sertraline will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Monitor Closely (1) tadalafil increases effects of silodosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of sotalol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of spironolactone by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) St John’s Wort will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Avoid combination in pulmonary HTN patients. For patients with ED, monitor response to tadalafil carefully because of potential for decreased effectiveness.

Monitor Closely (1) stiripentol, tadalafil. 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.

Monitor Closely (1) tadalafil, tamsulosin. Either increases effects of the other by additive vasodilation. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tazemetostat will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tecovirimat will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.

Monitor Closely (1) tadalafil increases effects of telmisartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of terazosin by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tetracycline will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. CYP3A4 inhibitors may reduce tadalafil clearance increasing systemic exposure to tadalafil; increased levels may result in increased associated adverse events.

Monitor Closely (1) tadalafil increases effects of timolol by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tipranavir will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. For ED limit tadalafil to max of 2.5 mg/day (for daily use) or 10 mg dose every 72 hr (for use as needed). Avoid concurrent use of tadalafil for pulmonary HTN in patients taking strong CYP3A4 inhibitors.

Monitor Closely (1) tobramycin inhaled and tadalafil both increase nephrotoxicity and/or ototoxicity. Modify Therapy/Monitor Closely. Avoid concurrent or sequential use to decrease risk for ototoxicity

Monitor Closely (1) topiramate will decrease the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Monitor Closely (1) tadalafil increases effects of torsemide by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of trandolapril by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) tadalafil increases effects of triamterene by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Serious – Use Alternative (1) tucatinib will increase the level or effect of tadalafil 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.

Monitor Closely (1) tadalafil increases effects of valsartan by pharmacodynamic synergism. Use Caution/Monitor. Risk of hypotension.

Monitor Closely (1) vardenafil, tadalafil. Other (see comment). Use Caution/Monitor. Comment: Avoid combination; duplicate therapy is not recommended.

Monitor Closely (1) verapamil will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Risk of hypotension.

Contraindicated (1) tadalafil, vericiguat. Either increases effects of the other by pharmacodynamic synergism. Contraindicated. Coadministration of vericiguat with PDE-5 inhibitors may result in additive hypotensive effects.

Monitor Closely (1) voriconazole will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Serious – Use Alternative (1) voxelotor will increase the level or effect of tadalafil 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.

Monitor Closely (1) zafirlukast will increase the level or effect of tadalafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.

Adverse Effects

Respiratory tract infection (3-13%)

Nasal congestion (≤9%)

Gastroesophageal reflux disease (1-3%)

Genitourinary tract infection (≤2%)

Pregnancy & Lactation

Pregnancy

Limited data from case series with use in pregnant women have not identified a drug-associated risk of major birth defects, miscarriage or adverse maternal or fetal outcomes

Pregnant women with untreated pulmonary arterial hypertension are at risk for heart failure, stroke, preterm delivery, and maternal and fetal death

Animal data

  • In animal reproduction studies, no adverse developmental effects were observed with oral administration to pregnant rats or mice during organogenesis at exposures 7 times the exposure at maximum recommended human dose (MRHD) of 40 mg/day based on AUC

Lactation

There are no data on presence of drug and/or its metabolites in human milk, effects on breastfed child, or on milk production; drug and/or its metabolites are present in milk of lactating rats at concentrations approximately 2.4-times that found in the plasma; when a drug is present in animal milk, it is likely that the drug will be present in human milk

Pregnancy Categories

A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

NA: Information not available.

Pharmacology

Mechanism of Action

Erectile dysfunction: Inhibits PDE-5, increasing cyclic guanosine monophosphate (cGMP) to allow smooth-muscle relaxation and inflow of blood into corpus cavernosum

Pulmonary arterial hypertension (PAH): Inhibits PDE-5, increasing cGMP to allow relaxation of pulmonary vascular smooth-muscle cells and vasodilation of pulmonary vasculature

Absorption

Peak plasma time: Erectile dysfunction, 0.5-6 hr; PAH, 2-8 hr

Distribution

Protein bound: 94%

Vd: Erectile dysfunction, 63 L; PAH, 77 L

Metabolism

Metabolized in liver by CYP3A4

Elimination

Half-life: Erectile dysfunction, 15-17.5 hr; PAH (not on bosentan), 35 hr

Total body clearance: Erectile dysfunction, 2.5 L/hr; PAH (not on bosentan), 1.6 L/hr

Excretion: Feces (61%), urine (36%)

Administration

Oral Administration

Erectile dysfunction (PRN use): Take before anticipated sexual activity

Erectile dysfunction (once-daily use): Take at approximately same time each day without regard to timing of sexual activity

Images

Copyright © 2010 First DataBank, Inc.

Patient Handout

COMMON BRAND NAME(S): Cialis

USES: Tadalafil is used to treat male sexual function problems (impotence or erectile dysfunction-ED). In combination with sexual stimulation, tadalafil works by increasing blood flow to the penis to help a man get and keep an erection.Tadalafil is also used to treat the symptoms of an enlarged prostate (benign prostatic hyperplasia-BPH). It helps to relieve symptoms of BPH such as difficulty in beginning the flow of urine, weak stream, and the need to urinate frequently or urgently (including during the middle of the night). Tadalafil is thought to work by relaxing the smooth muscle in the prostate and bladder.This drug does not protect against sexually transmitted diseases (such as HIV, hepatitis B, gonorrhea, syphilis). Practice “safe sex” such as using latex condoms. Consult your doctor or pharmacist for more details.

HOW TO USE: Read the Patient Information Leaflet provided by your pharmacist before you start taking tadalafil and each time you get a refill. If you have any questions, ask your doctor or pharmacist.Take this medication by mouth, with or without food, as directed by your doctor. Do not take tadalafil more often than once daily.The manufacturer directs to swallow this medication whole. However, many similar drugs (immediate-release tablets) can be split/crushed. Follow your doctor’s directions on how to take this medication.The dosage is based on your medical condition, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).To treat the symptoms of BPH, take this medication as directed by your doctor, usually once a day. If you are also taking finasteride with this medication to treat symptoms of BPH, talk with your doctor about how long you should continue taking this medication.To treat erectile dysfunction-ED, there are 2 ways that tadalafil may be prescribed. Your doctor will determine which is the best way for you to take tadalafil. Follow your doctor’s directions exactly since your dosage depends on how you are taking it. The first way is to take it as needed, usually at least 30 minutes before sexual activity. Tadalafil’s effect on sexual ability may last up to 36 hours.The second way to treat ED is to take tadalafil regularly, once a day every day. If you take it this way, you may attempt sexual activity at any time between your doses.If you are taking tadalafil to treat both ED and BPH, take it as directed by your doctor, usually once a day. You may attempt sexual activity at any time between your doses.If you are taking tadalafil once daily for BPH, or for ED, or for both, take it regularly to get the most benefit from it. To help you remember, take it at the same time each day.Tell your doctor if your condition does not improve or if it worsens.

SIDE EFFECTS: Headache, stomach upset, back pain, muscle pain, stuffy nose, flushing, or dizziness may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Sexual activity may put extra strain on your heart, especially if you have heart problems. If you have heart problems and experience any of these serious side effects while having sex, stop and get medical help right away: severe dizziness, fainting, chest/jaw/left arm pain, nausea.Rarely, sudden decreased vision, including permanent blindness, in one or both eyes (NAION) may occur. If this serious problem occurs, stop taking tadalafil and get medical help right away. You have a slightly greater chance of developing NAION if you have heart disease, diabetes, high cholesterol, certain other eye problems (“crowded disk”), high blood pressure, if you are over 50, or if you smoke.Rarely, a sudden decrease or loss of hearing, sometimes with ringing in the ears and dizziness, may occur. Stop taking tadalafil and get medical help right away if these effects occur.In the rare event you have a painful or prolonged erection lasting 4 or more hours, stop using this drug and get medical help right away, or permanent problems could occur.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada – Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

PRECAUTIONS: Before taking tadalafil, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: heart problems (such as heart attack or life-threatening irregular heartbeat in the past 6 months, chest pain/angina, heart failure), stroke in the past 6 months, kidney disease, liver disease, high or low blood pressure, dehydration, penis conditions (such as angulation, fibrosis/scarring, Peyronie’s disease), history of painful/prolonged erection (priapism), conditions that may increase the risk of priapism (such as sickle cell anemia, leukemia, multiple myeloma), eye problems (such as retinitis pigmentosa, sudden decreased vision, NAION), bleeding disorders, active stomach ulcers.This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).This brand of the drug is not usually used in women. During pregnancy, tadalafil should be used only when clearly needed. Discuss the risks and benefits with your doctor.It is unknown if this medication passes into breast milk. Consult your doctor before breast-feeding.

DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.A product that may interact with this drug is: riociguat.Tadalafil can cause a serious drop in your blood pressure when used with nitrates, which can lead to dizziness, fainting, and rarely heart attack or stroke. Do not use any of the following with tadalafil or within 48 hours of your last dose of tadalafil: certain drugs used to treat chest pain/angina (nitrates such as nitroglycerin, isosorbide), recreational drugs called “poppers” containing amyl or butyl nitrite.If you are also taking an alpha blocker medication (such as doxazosin, tamsulosin) to treat an enlarged prostate/BPH or high blood pressure, your blood pressure may get too low which can lead to dizziness or fainting. Your doctor may start treatment with a lower dose of tadalafil or adjust your alpha blocker medication to minimize your risk of low blood pressure.Other medications can affect the removal of tadalafil from your body, which may affect how tadalafil works. Examples include azole antifungals (such as itraconazole, ketoconazole), macrolide antibiotics (such as clarithromycin, erythromycin), HIV protease inhibitors (such as fosamprenavir), rifampin, ritonavir, among others.Do not take this medication with any other product that contains tadalafil or other similar medications used to treat erectile dysfunction-ED or pulmonary hypertension (such as sildenafil, vardenafil).

OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

NOTES: Do not share this medication with others.

MISSED DOSE: If you are taking this medication on a regular schedule and you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Information last revised August 2022. Copyright(c) 2022 First Databank, Inc.

IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.