View source for Sildenafil

==Administration==
*Type: PDE-5 inhibitor
*Dosage Forms:
*Routes of Administration: PO, IV
*Common Trade Names: Viagra, [https://fildena.net Fildena], Revatio

==Adult Dosing==
*Pulmonary hypertension: 5-20mg PO TID or 2.5-10 mg IV bolus TID
*Erectile dysfunction: 25-100mg PO 1hr prior to sexual activity, max once daily

==Pediatric Dosing==
''Not generally recommended for chronic use in pediatric patients, but is used off-label''

==Special Populations==
*[[Drug pregnancy categories|Pregnancy Rating]]: B
*Lactation risk: Infant risk cannot be ruled out
*Renal dosing: no adjustment 
*Hepatic dosing: no adjustment for mild-moderate impairment

==Contraindications==
*Allergy to class/drug
*Concurrent regular or intermittent use of any organic nitrates 
*Concomitant use with HIV protease inhibitors or elvitegravir/cobicistat/tenofovir/emtricitabine
*Concomitant use with [[riociguat]] or any other guanylate cyclase stimulator

==Adverse Reactions==
===Serious===
*Myocardial infaction
*Sickle cell vasoocclusive crisis
*Ischemic optic neuropathy, retinal hemorrhage
*Hearing loss
*Priapism
===Common===
*Headache
*Insomnia
*Visual disturbance
*Erythema, flushing
*Indigestion
*Epistaxis, nasal congestion, rhinorrhea

==Pharmacology==
*Half-life: 4h
*Metabolism: Hepatic: CYP3A4 (major) and CYP2C9 (minor)
*Excretion: Mostly fecal

==Mechanism of Action==
*Inhibits cGMP specific phosphodiesterase type-5 (PDE5) in smooth muscle→ less cGMP breakdown→ more cGMP within vascular smooth muscle→ vascular smooth muscle relaxation→ vasodilation

==Comments==


==See Also==
*[[Pulmonary hypertension]]

==References==
<references/>

[[Category:Pharmacology]]