Sildenafil
- Atc Codes:G04BE03
- CAS Codes:171599-83-0#139755-83-2
- PHARMGKB ID:171599-83-0#139755-83-2
Table of contents
- Brand Names
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Unlabeled Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Caution and personalized dose adjustment in patients with the following genotypes
- Other genes that may be involved
- Substrate of
- Inhibits
- Induces
- Drug Interactions
- Nutrition/Nutraceutical Interactions
- Dosage
- Pharmacokinetics and Pharmacodynamics
- Special Considerations
Brand Names
Europe
Austria: Revatio, Viagra, Vizarsil; Belgium: Revatio, Viagra; Bulgaria: Revatio, Viagra; Cyprus: Revatio, Viagra; Czech Republic: Revatio, Sildenafil, Viagra, Vigrande, Vizarsin; Denmark: Revatio, Viagra; Estonia: Revatio, Sildenafil, Viagra, Vigrande, Vizarsin; Finland: Revatio, Viagra, Vizarsin; France: Revatio, Viagra; Germany: Revatio, Viagra, Vizarsin; Greece: Revatio, Viagra; Hungary: Revatio, Sildenafil, Viagra; Ireland: Revatio, Sidena, Sildenafil, Viagra, Vizarsin; Italy: Revatio, Viagra; Latvia: Revatio, Sildenafil, Viagra, Vizarsin; Lithuania: Revatio, Viagra; Luxembourg: Revatio, Sildenafil, Viagra, Vizarsin; Malta: Revatio, Viagra, Vizarsin; Netherlands: Revatio, Sildenafil, Viagra, Vizarsin; Poland: Maxigra, Revatio, Sildenafil, Viagra, Vizarsin; Portugal: Revatio, Sildenafil, Viagra, Vizarsin; Romania: Revatio, Sildenafil, Viagra, Vizarsin; Slovakia: Revatio, Sildefanil, Viagra, Vigrande, Vizarsin; Slovenia: Revatio, Sildenafil, Viagra, Vizarsin; Spain: Revatio, Viagra, Vizarsin; Sweden: Revatio, Sildenafil, Viagra, Vizarsin; UK: Revatio, Viagra.
North America
Canada: Revatio, Viagra; USA: Revatio, Viagra.
Latin America
Argentina: Activil, Almaximo, Anaus, Bifort, Cagno, Egomax, Erectol, Expit, Falic, File, Firmel, Forzak, Gimonte Sildenafil, Gladium, Incresil, Juvigor, Labsamax, Lorbinafil, Lumix, Magnus, Maxdosa, Nexofil, Nitro Rontang, Openvas-LKM, Paramen, Permitil, Segurex, Sildefil, Sildenafil, Super-O, Tecnomax, Viagra, Vigor Plus, Vimax, Virilon, Viripotens, Vorst; Brazil: Revatio, Viagra; Mexico: Apodefil, Patrex, Viagra.
Asia
Japan: Revatio, Viagra.
Drug combinations
Chemistry
Sildenafil Citrate: C~22~H~30~N~6~O~4~S C~6~H~8~O~7~. Mw: 666.70. (1) Piperazine, 1-[[3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-5-yl)-4-ethoxyphenyl]sulfonyl]-4-methyl-, 2-hydroxy-1,2,3-propanetricarboxylate (1:1); (2) 1-[[3-(6,7-Dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-5-yl)-4-ethoxyphenyl]sulfonyl]-4-methylpiperazine citrate (1:1). CAS-171599-83-0; CAS-139755-83-2 (sildenafil)(1997).

Pharmacologic Category
Vasodilating Agents; Phosphodiesterase Inhibitors; Phosphodiesterase-5 Enzyme Inhibitor. Respiratory Smooth Muscle Relaxants. (ATC-Code: G04BE03).
Mechanism of action
Selective phosphodiesterase-type 5 (PDE-5) inhibitor. PDE-5 is found in pulmonary vascular smooth muscle, vascular and visceral smooth muscle, corpus cavernosum of penis and clitoris, and platelets. PDE-5 is responsible for degradation of cyclic guanosine monophosphate (cGMP). Normally, nitric oxide (NO) activates enzyme guanylate cyclase, which increases levels of cGMP. cGMP produces smooth muscle relaxation. Inhibition of PDE-5 by sildenafil increases cellular levels of cGMP. Increased levels of cGMP potentiate vascular smooth muscle relaxation, particularly in lung where PDE-5 is found in high concentrations. In pulmonary arterial hypertension, sildenafil causes vasodilation in pulmonary vasculature and, to a lesser extent, in systemic circulation. In erectile dysfunction, sildenafil does not directly cause penile erections, but affects response to sexual stimulation. Sildenafil enhances effect of NO by inhibiting PDE-5 and increasing levels of cGMP in corpus cavernosum.
Therapeutic use
Pulmonary arterial hypertension, persistent pulmonary hypertension of newborn refractory to treatment with inhaled nitric oxide, secondary pulmonary hypertension following cardiac surgery. To facilitate weaning from nitric oxide. Erectile dysfunction.
Pregnancy and lactiation implications
Teratogenic effects not observed in animals. There are no adequate studies in pregnant women. Excretion in breast milk unknown (use caution).
Unlabeled use
Pulmonary arterial hypertension in children.
Contraindications
Known hypersensitivity to sildenafil or any ingredient in the formulation. Concomitant use of organic nitrates or nitrites. Should not be used for treatment of erectile dysfunction in men for whom sexual activity is inadvisable due to their underlying cardiovascular status.
Warnings and precautions
May cause dose-related impairment of color discrimination (caution in retinitis pigmentosa). Sudden decrease or loss of hearing reported. Decreases in blood pressure may occur due to vasodilator effects. Vision loss may occur rarely and be a sign of nonarteritic anterior ischemic optic neuropathy (risk may be increased with history of vision loss, low cup-to-disc ratio, coronary artery disease, diabetes, hypertension, hyperlipidemia, smoking, and >50 years of age). Painful erection >6 hours in duration. Use with caution in anatomical deformation of the penis (angulation, cavernosal fibrosis, or Peyronie’s disease), and in bleeding disorders. In vitro studies suggested decreased effect on platelet aggregation. Use with caution in hypotension (<90/50 mm Hg), uncontrolled hypertension (>170/110 mm Hg), life-threatening arrhythmias, stroke or myocardic infarction within last 6 months, cardiac failure or coronary artery disease causing unstable angina. Use caution in left ventricular outflow obstruction (e.g. aortic stenosis). Use with caution in hepatic impairment, in active peptic ulcer disease, in renal impairment, and in patients taking α-blockers (may cause symptomatic hypotension) or strong CYP3A4 inhibitors. Concomitant (regularly/intermittently) use with all forms of nitrates contraindicated. Safety and efficacy with other treatments for erectile dysfunction not established; use not recommended. Efficacy with concurrent bosentan therapy not evaluated (use with caution).