Sildenafil Citrate: Mechanism of Action and How It Works
Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels rifapentine 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 rilzabrutinibrilzabrutinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Follow substrate recommendations for use with moderate CYP3A inhibitors rilzabrutinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Follow substrate recommendations for use with moderate CYP3A inhibitors Either increases effects of the other by pharmacodynamic synergism. Coadministration of sepiapterin with drugs affecting nitric oxide-mediated relaxation may cause additive vasodilation and further reduce blood pressure.
What other drugs will affect sildenafil?
anastrozoleanastrozole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. anastrozole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. cyclophosphamidecyclophosphamide will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. cyclophosphamide will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. drospirenonedrospirenone will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
Oral Administration
drospirenone will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. labetalolsildenafil increases effects of labetalol by pharmacodynamic synergism. sildenafil increases effects of labetalol by pharmacodynamic synergism. larotrectiniblarotrectinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. larotrectinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
Interaction médicamenteuse
macitentanmacitentan increases levels of sildenafil by unspecified interaction mechanism. Systemic exposure of steady-state sildenafil (20 mg TID) increased by 15% during coadministration of macitentan (10 mg/day); this change is not considered clinically relevant. macitentan increases levels of sildenafil by unspecified interaction mechanism. Possible additive vasorelaxation, leading to low blood pressure. 50-mg doseHeadache (21%)Flushing (19%)100-mg dose H5Headache (28%)Flushing (18%)Dyspepsia (17%)Abnormal vision (11%) 25-mg doseFlushing (10%)Nasal congestion (4%)Dyspepsia (3%)Back pain (3%)Dizziness (3%)Myalgia (2%)Nausea (2%)Abnormal vision (1%)Rash (1%) 50-mg doseDyspepsia (9%)Nasal congestion (4%)Back pain (4%)Dizziness (4%)Nausea (3%)Abnormal vision (2%)Myalgia (2%)Rash (2%) 100-mg doseNasal congestion (9%)Back pain (4%)Myalgia (4%)Nausea (3%)Dizziness (3%)Rash (3%) <2% with potential causal relationshipBody as a whole: Face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injuryCardiovascular: Angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathyDigestive: Vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitisHemic and lymphatic: Anemia and leukopeniaMetabolic and nutritional: Thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremiaMusculoskeletal: Arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitisNervous: Ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesiaRespiratory: Asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increasedSkin and appendages: Urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitisSpecial senses: Sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyesUrogenital: Cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia Body as a whole: Face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injury Cardiovascular: Angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy Digestive: Vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitis Metabolic and nutritional: Thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremia Musculoskeletal: Arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis Nervous: Ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesia Respiratory: Asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increased Skin and appendages: Urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis Special senses: Sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyes Urogenital: Cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia Cardiovascular and cerebrovascular: Serious cardiovascular (CV), cerebrovascular, and vascular events, including myocardial infarction, sudden cardiac death, ventricular arrhythmia, cerebrovascular hemorrhage, transient ischemic attack, hypertension, subarachnoid and intracerebral hemorrhages, and pulmonary hemorrhage (most, but not all, of these patients had preexisting CV risk factors) Hemic and lymphatic: vaso-occlusive crisis: In a small, prematurely terminated study of sildenafil in patients with pulmonary arterial hypertension (PAH) secondary to sickle cell disease, vaso-occlusive crises requiring hospitalization were commonly reported Nervous: Seizure, seizure recurrence, anxiety, and transient global amnesia Hearing: Cases of sudden decrease or loss of hearing reported postmarketing in temporal association with PDE5 inhibitors Ocular: Diplopia, temporary vision loss/decreased vision, ocular redness or bloodshot appearance, ocular burning, ocular swelling/pressure, increased intraocular pressure, retinal edema, retinal vascular disease or bleeding, and vitreous traction/detachment Nonarteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision (reported rarely) Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension Coadministration with nitrates (either regularly and/or intermittently) and nitric oxide donors Consistent with the effects of PDE5 inhibition on the nitric oxide/cyclic guanosine monophosphate pathway, PDE5 inhibitors may potentiate the hypotensive effects of nitrates A suitable time interval following PDE5 dosing for the safe administration of nitrates or nitric oxide donors has not been determined Elicits vasodilatory properties, resulting in mild and transient decreases in blood pressure; monitor for hypotension Use with caution in patients with anatomic deformation of penis (eg, angulation, cavernosal fibrosis, or Peyronie disease), conditions potentially predisposing to priapism (eg, sickle cell anemia, multiple myeloma, or leukemia), cardiovascular disease, bleeding disorders, active peptic ulcer disease, liver disease, renal impairment, multidrug antihypertensive regimens, retinitis pigmentosa, concomitant use of CYP3A4 inhibitors Pulmonary vasodilators may significantly worsen cardiovascular status of patients with pulmonary veno-occlusive disease Sudden decrease or loss of hearing, which may be accompanied by tinnitus and dizziness Stop sildenafil and seek medical care if a sudden loss of vision occurs in 1 or both eyes, which could be a sign of nonarteritic anterior ischemic optic neuropathy (NAION); use with caution, and only when the anticipated benefits outweigh the risks, most patients had underlying anatomic or vascular risk factors for developing NAION, including low cup to disc ratio (“crowded disc”); advise patients to seek immediate medical attention in the event of a sudden loss of vision May cause dose-related impairment of color discrimination; use in patients with retinitis pigmentosa not recommended Potential for cardiac risk with sexual activity in patients with preexisting cardiovascular disease; therefore, treatment for erectile dysfunction generally should not be instituted in men for whom sexual activity is inadvisable because of their underlying cardiovascular status Evaluate underlying causes of erectile dysfunction or BPH before initiating therapy In small, prematurely terminated study of patients with PAH secondary to sickle-cell disease, vaso-occlusive crises requiring hospitalization were more commonly reported by patients who received sildenafil than by those randomized to placebo; effectiveness of sildenafil in PAH secondary to sickle-cell anemia has not been established; the clinical relevance to men treated for erectile dysfunction with sildenafil is not known Epistaxis occurred in 13% of patients with PAH secondary to connective tissue disease (eg, scleroderma); this effect was not seen in idiopathic PAH; incidence was also higher in those receiving concomitant PO vitamin K antagonist the sotalolsotalol increases effects of sildenafil by additive vasodilation.
| Product | Dosage | Quantity + Bonus | Price | |
|---|---|---|---|---|
| Viagra Generic | 100mg | 20 Pills | 45.58€ 43.41€ | |
| Viagra Generic | 150mg | 30 + 2 Pills | 72.32€ 68.88€ | |
| Viagra Generic | 100mg | 120 + 6 Pills | 149.50€ 142.38€ | |
| Viagra Generic | 50mg | 120 + 6 Pills | 129.64€ 123.47€ | |
| Viagra Generic | 100mg | 60 + 4 Pills | 96.36€ 91.77€ | |
| Viagra Generic | 50mg | 270 + 8 Pills | 198.48€ 189.03€ | |
| Viagra Generic | 100mg | 10 Pills | 28.91€ 27.53€ | |
| Viagra Generic | 25mg | 20 Pills | 37.74€ 35.94€ | |
| Viagra Generic | 100mg | 180 + 8 Pills | 199.37€ 189.88€ | |
| Viagra Generic | 150mg | 270 + 10 Pills | 326.61€ 311.06€ | |
| Kamagra Oral Jelly | 100mg | 10 Sachets | 54.55€ 51.95€ | |
| Viagra Generic | 25mg | 360 + 10 Pills | 213.68€ 203.50€ | |
| Viagra Generic | 100mg | 90 + 6 Pills | 129.02€ 122.88€ | |
| Viagra Generic | 25mg | 120 + 6 Pills | 125.56€ 119.58€ | |
| Kamagra Oral Jelly | 100mg | 110 + 9 Sachets | 334.87€ 318.92€ |
sotalol increases effects of sildenafil by additive vasodilation. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. suzetriginesuzetrigine decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
Other uses for this medicine
Does sildenafil interact with foods or drinks?
Monitor patients for loss of therapeutic effect of sensitive CYP3A substrates with narrow therapeutic indexes when coadministered with suzetrigine.
- Sildenafil citrate was approved by the FDA in 1998.
- Its discovery revolutionized the treatment of erectile dysfunction.
- The medication requires sexual stimulation to be effective.
- It is not an aphrodisiac; it facilitates natural response.
- Overdose symptoms may include severe hypotension.
- Recreational use of sildenafil without prescription is risky.
- Combining with alcohol can increase side effects.
- It should be stored at room temperature away from moisture.
Consider modifying dose of sensitive substrate according to prescribing recommendations. suzetrigine decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
| Side Effect | Frequency | Severity | Management Tips |
|---|---|---|---|
| Headache | Very common | Mild to moderate | Analgesics if needed |
| Flushing | Common | Mild | Cool environment, hydration |
| Dyspepsia | Common | Mild | Dietary adjustments |
| Nasal Congestion | Less common | Mild | Decongestants if necessary |
| Dizziness | Less common | Mild | Avoid sudden movements |
tecovirimattecovirimat will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Monitor sildenafil pick up sensitive CYP3A4 substrates for effectiveness if coadministered.
| Country | Legal Status | Prescription Requirement | Notes |
|---|---|---|---|
| USA | Prescription-only medication | Yes | FDA approved |
| UK | Prescription-only | Yes | MHRA regulated |
| India | Over-the-counter and prescription | Both are possible | Varies by state |
| Australia | Prescription only | Yes | TGA regulated |
tecovirimat will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. timololtimolol increases effects of sildenafil by additive vasodilation. timolol increases effects of sildenafil by additive vasodilation. tipranavirtipranavir increases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Increased risk of priapism, hypotension, and other adverse effects. tipranavir increases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. tobramycin inhaledtobramycin inhaled and sildenafil both increase nephrotoxicity and/or ototoxicity. Avoid concurrent or sequential use to decrease risk for ototoxicity tobramycin inhaled and sildenafil both increase nephrotoxicity and/or ototoxicity. Avoid concurrent or sequential use to decrease risk for ototoxicity verapamilverapamil will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. verapamil will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. voriconazolevoriconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. voriconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
- Sildenafil works by inhibiting phosphodiesterase type 5 enzyme.
- This inhibition increases cGMP levels in the body.
- Elevated cGMP leads to smooth muscle relaxation.
- It promotes vasodilation in the corpus cavernosum.
- This process facilitates an erection during sexual activity.
- The drug’s pharmacokinetics allow for rapid absorption.
- Food intake can influence absorption rate.
- It is effective in men of various ages.
zafirlukastzafirlukast will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. zafirlukast will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. acetazolamideacetazolamide sildenafil 12 5 mg will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. acetazolamide will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. anastrozoleanastrozole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. anastrozole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. cyclophosphamidecyclophosphamide will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. cyclophosphamide will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
| Age Group | Approved Usage | Recommended Dose | Additional Comments |
|---|---|---|---|
| 18-65 years | Erectile Dysfunction, PAH | 50-100 mg as needed | Adjust based on response |
| Above 65 years | Use with caution, lower doses possibly | Start at 25-50 mg | Monitor for side effects |
| Under 18 years | Not approved | N/A | Not indicated for minors |
drospirenonedrospirenone will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. drospirenone will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. labetalolsildenafil increases effects of labetalol by pharmacodynamic synergism. sildenafil increases effects of labetalol by pharmacodynamic synergism. larotrectiniblarotrectinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
Related/similar drugs
Potent CYP3A4 inducers are expected to cause substantial decreases in sildenafil plasma levels rifapentine 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 rilzabrutinibrilzabrutinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Follow substrate recommendations for use with moderate CYP3A inhibitors rilzabrutinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Follow substrate recommendations for use with moderate CYP3A inhibitors Either increases effects of the other by pharmacodynamic synergism. Coadministration of sepiapterin with drugs affecting nitric oxide-mediated relaxation may cause additive vasodilation and further reduce blood pressure.
Professional resources
sotalolsotalol increases effects of sildenafil by additive vasodilation. sotalol increases effects of sildenafil by additive vasodilation. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. suzetriginesuzetrigine decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Monitor patients for loss of therapeutic effect of sensitive CYP3A substrates with narrow therapeutic indexes when coadministered with suzetrigine.
Sildenafil may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
Consider modifying dose of sensitive substrate according to prescribing recommendations. suzetrigine decreases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. tecovirimattecovirimat will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Monitor sildenafil pick up sensitive CYP3A4 substrates for effectiveness if coadministered. tecovirimat will decrease the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. larotrectinib will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. macitentanmacitentan increases levels of sildenafil by unspecified interaction mechanism.
3. Downsides
timololtimolol increases effects of sildenafil by additive vasodilation. timolol increases effects of sildenafil by additive vasodilation. tipranavirtipranavir increases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Increased risk of priapism, hypotension, and other adverse effects. tipranavir increases levels of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
Sildenafil vs. tadalafil
tobramycin inhaledtobramycin inhaled and sildenafil both increase nephrotoxicity and/or ototoxicity. Avoid concurrent or sequential use to decrease risk for ototoxicity tobramycin inhaled and sildenafil both increase nephrotoxicity and/or ototoxicity. Avoid concurrent or sequential use to decrease risk for ototoxicity verapamilverapamil will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. verapamil will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. voriconazolevoriconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism.
What should I tell my healthcare provider before taking sildenafil?
voriconazole will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. zafirlukastzafirlukast will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. zafirlukast will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. acetazolamideacetazolamide sildenafil 12 5 mg will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. acetazolamide will increase the level or effect of sildenafil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Systemic exposure of steady-state sildenafil (20 mg TID) increased by 15% during coadministration of macitentan (10 mg/day); this change is not considered clinically relevant. macitentan increases levels of sildenafil by unspecified interaction mechanism. Possible additive vasorelaxation, leading to low blood pressure. 50-mg doseHeadache (21%)Flushing (19%)100-mg dose H5Headache (28%)Flushing (18%)Dyspepsia (17%)Abnormal vision (11%) 25-mg doseFlushing (10%)Nasal congestion (4%)Dyspepsia (3%)Back pain (3%)Dizziness (3%)Myalgia (2%)Nausea (2%)Abnormal vision (1%)Rash (1%) 50-mg doseDyspepsia (9%)Nasal congestion (4%)Back pain (4%)Dizziness (4%)Nausea (3%)Abnormal vision (2%)Myalgia (2%)Rash (2%) 100-mg doseNasal congestion (9%)Back pain (4%)Myalgia (4%)Nausea (3%)Dizziness (3%)Rash (3%) <2% with potential causal relationshipBody as a whole: Face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injuryCardiovascular: Angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathyDigestive: Vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitisHemic and lymphatic: Anemia and leukopeniaMetabolic and nutritional: Thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremiaMusculoskeletal: Arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitisNervous: Ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesiaRespiratory: Asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increasedSkin and appendages: Urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitisSpecial senses: Sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyesUrogenital: Cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia Body as a whole: Face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injury Cardiovascular: Angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy Digestive: Vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitis Metabolic and nutritional: Thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremia Musculoskeletal: Arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis Nervous: Ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesia Respiratory: Asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increased Skin and appendages: Urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis Special senses: Sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyes Urogenital: Cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia Cardiovascular and cerebrovascular: Serious cardiovascular (CV), cerebrovascular, and vascular events, including myocardial infarction, sudden cardiac death, ventricular arrhythmia, cerebrovascular hemorrhage, transient ischemic attack, hypertension, subarachnoid and intracerebral hemorrhages, and pulmonary hemorrhage (most, but not all, of these patients had preexisting CV risk factors) Hemic and lymphatic: vaso-occlusive crisis: In a small, prematurely terminated study of sildenafil in patients with pulmonary arterial hypertension (PAH) secondary to sickle cell disease, vaso-occlusive crises requiring hospitalization were commonly reported Nervous: Seizure, seizure recurrence, anxiety, and transient global amnesia Hearing: Cases of sudden decrease or loss of hearing reported postmarketing in temporal association with PDE5 inhibitors Ocular: Diplopia, temporary vision loss/decreased vision, ocular redness or bloodshot appearance, ocular burning, ocular swelling/pressure, increased intraocular pressure, retinal edema, retinal vascular disease or bleeding, and vitreous traction/detachment Nonarteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision (reported rarely) Soluble guanylate cyclase (sGC) stimulators (eg, riociguat); concomitant use can cause hypotension Coadministration with nitrates (either regularly and/or intermittently) and nitric oxide donors Consistent with the effects of PDE5 inhibition on the nitric oxide/cyclic guanosine monophosphate pathway, PDE5 inhibitors may potentiate the hypotensive effects of nitrates A suitable time interval following PDE5 dosing for the safe administration of nitrates or nitric oxide donors has not been determined Elicits vasodilatory properties, resulting in mild and transient decreases in blood pressure; monitor for hypotension Use with caution in patients with anatomic deformation of penis (eg, angulation, cavernosal fibrosis, or Peyronie disease), conditions potentially predisposing to priapism (eg, sickle cell anemia, multiple myeloma, or leukemia), cardiovascular disease, bleeding disorders, active peptic ulcer disease, liver disease, renal impairment, multidrug antihypertensive regimens, retinitis pigmentosa, concomitant use of CYP3A4 inhibitors Pulmonary vasodilators may significantly worsen cardiovascular status of patients with pulmonary veno-occlusive disease Sudden decrease or loss of hearing, which may be accompanied by tinnitus and dizziness Stop sildenafil and seek medical care if a sudden loss of vision occurs in 1 or both eyes, which could be a sign of nonarteritic anterior ischemic optic neuropathy (NAION); use with caution, and only when the anticipated benefits outweigh the risks, most patients had underlying anatomic or vascular risk factors for developing NAION, including low cup to disc ratio (“crowded disc”); advise patients to seek immediate medical attention in the event of a sudden loss of vision May cause dose-related impairment of color discrimination; use in patients with retinitis pigmentosa not recommended Potential for cardiac risk with sexual activity in patients with preexisting cardiovascular disease; therefore, treatment for erectile dysfunction generally should not be instituted in men for whom sexual activity is inadvisable because of their underlying cardiovascular status Evaluate underlying causes of erectile dysfunction or BPH before initiating therapy In small, prematurely terminated study of patients with PAH secondary to sickle-cell disease, vaso-occlusive crises requiring hospitalization were more commonly reported by patients who received sildenafil than by those randomized to placebo; effectiveness of sildenafil in PAH secondary to sickle-cell anemia has not been established; the clinical relevance to men treated for erectile dysfunction with sildenafil is not known Epistaxis occurred in 13% of patients with PAH secondary to connective tissue disease (eg, scleroderma); this effect was not seen in idiopathic PAH; incidence was also higher in those receiving concomitant PO vitamin K antagonist the
