14 CLINICAL STUDIES

Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels doxazosinsildenafil increases effects of doxazosin by pharmacodynamic synergism. sildenafil 20mg sildenafil increases effects of doxazosin by pharmacodynamic synergism. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels eslicarbazepine acetate will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels fexinidazolefexinidazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Coadministration may increase risk for adverse effects of CYP3A4 substrates. fexinidazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. ivosidenibivosidenib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid coadministration of sensitive CYP3A4 substrates with ivosidenib or replace with alternative therapies. If coadministration is unavoidable, monitor patients for loss of therapeutic effect of these drugs. ivosidenib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

12.2 Pharmacodynamics

clarithromycin will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. conivaptanconivaptan will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Delay initiation of treatment with any CYP3A4 substrates for at least 7 days following discontinuation of conivaptan. conivaptan will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. crizotinibcrizotinib increases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

Sildenafil vs. tadalafil

If concomitant use of strong CYP3A inhibitors is unavoidable, reduce crizotnib to 250 mg PO qDay. After discontinuation of a strong CYP3A inhibitor, resume crizotinib dose used prior to initiating the strong CYP3A4 inhibitor. crizotinib increases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. dabrafenibdabrafenib will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels dabrafenib will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. ketoconazoleketoconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Coadministration with strong CYP3A4 inhibitors and sildenafil (for pulmonary arterial hypertension) is not recommended. When used for erectile dysfunction, consider reducing initial sildenafil dose of 25 mg in patients also taking a strong CYP3A4 inhibitor and monitor for sildenafil toxicities (eg, dyspepsia, headache, hypotension).

ketoconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. lenacapavirlenacapavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Refer to the prescribing information of PDE5 inhibitors for dose recommendations. lenacapavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

Patient Assistance & Copay Programs for Sildenafil

apalutamide will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. asenapinesildenafil increases effects of asenapine by pharmacodynamic synergism. sildenafil increases effects of asenapine by pharmacodynamic synergism. ceritinibceritinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. ceritinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

Drug Interactions

chloramphenicolchloramphenicol will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. chloramphenicol will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. clarithromycinclarithromycin will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Coadministration of these phosphodiesterase inhibitors with clarithromycin, a CYP3A4 inhibitor is not recommended. Increased systemic exposure of these drugs may occur with clarithromycin; consider reduction of dosage for phosphodiesterase inhibitors. levoketoconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

• Common side effects include headaches, flushing, and nasal congestion.
• Rarely can cause vision changes, such as blurred vision or color tinge.
• Serious side effects require immediate medical attention.

lonafarniblonafarnib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

• Not suitable for individuals with severe heart or liver conditions.
• Always inform your healthcare provider of all medications being taken.
• Follow-up appointments ensure safe and effective use.

If coadministration unavoidable, monitor for adverse reactions and reduce CYP3A substrate dose in accordance with product labeling. lonafarnib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. lopinavirlopinavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. lopinavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

• Sildenafil 12.5 mg can improve confidence and quality of life.
• Patients should discuss potential drug interactions with their doctor.
• Be aware of potential side effects and report unusual symptoms promptly.

mifepristonemifepristone will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. mifepristone will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. mitotanemitotane decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Potent CYP3A4 sildenafil citrate drug inducers are expected to cause substantial decreases in sildenafil plasma levels. mitotane decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. nafcillinnafcillin will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels nafcillin will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Patients receiving indinavir with ritonavir should receive not more than 25 mg of sildenafil for treatment of erectile dysfunction in a 48-hour period, and patients receiving other protease inhibitors should use a lower initial sildenafil dose of 25 mg. Patient taking sildenafil for PAH with ritonavir is not recommended.

pentobarbitalpentobarbital will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels pentobarbital will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

Recent Updates on Sildenafil Research

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 within 24 hr of each other. Either increases effects of the other by pharmacodynamic synergism. Coadministration of vericiguat with PDE-5 inhibitors may result in additive hypotensive effects. alfuzosinsildenafil increases effects of alfuzosin by pharmacodynamic synergism. sildenafil increases effects of sildenafil 100mg blue pill alfuzosin by pharmacodynamic synergism.

Clinical monitoring

apalutamideapalutamide will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. 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. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels phenobarbitalphenobarbital will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

• Sildenafil 12.5 mg is contraindicated with nitrate medications.
• Alcohol can reduce effectiveness and increase side effect risk.
• Always follow your healthcare provider’s dosage instructions carefully.

Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels phenobarbital will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels phenoxybenzaminesildenafil increases effects of phenoxybenzamine by pharmacodynamic synergism. sildenafil increases effects of phenoxybenzamine by pharmacodynamic synergism. phentolaminesildenafil increases effects of phentolamine by pharmacodynamic synergism. sildenafil increases effects of phentolamine by pharmacodynamic synergism. phenytoinphenytoin will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels phenytoin will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

5.6 Combination with other PDE-5 Inhibitors

nelfinavirnelfinavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. nelfinavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Coadministration contraindicated if sildenafil used for pulmonary arterical hypertension. Reduce sildenafil dose if used for erectile dysfunction. nirmatrelvir/ritonavir will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.

Hypertension (Off-Label Use)

nitroglycerin rectalsildenafil increases effects of nitroglycerin rectal by additive vasodilation. 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. sildenafil increases effects of nitroglycerin rectal by additive vasodilation. Either increases effects of the other by additive vasodilation.