Its use is not studied in patients with severe hepatic impairment. They include dutasteride Avodart, Jalyn and finasteride Propecia, Proscar. Follow-up support: Make sure you can get the help you need if questions or concerns arise after ordering. Epistaxis was not observed in patients with idiopathic PAH. You can take this medicine with or without food 30 minutes before sex, depending on the dose.The usual dose is 50mg, when you need it. Do not take it more than once a day. The dose can be increased to mg or decreased to 25mg depending on its effect. Take sildenafil up to 4 hours before you want to have sex. For sildenafil to work properly, you’ll need to be sexually excited. Sildenafil oral tablet is available as a brand-name drug and as a generic drug. Brand names: Viagra, Revatio. Sildenafil comes in three forms: an oral tablet, an oral suspension (liquid), and an. Pfizer, the manufacturer of Viagra, offers a program that can help lower the cost of Viagra. For more information and to find out if you’re eligible for support, call or visit the.