Place the tablet on your tongue and allow it to melt. Vardenafil does not prevent pregnancy or the spread of sexually transmitted diseases such as human immunodeficiency virus HIV. The tablet will quickly dissolve. Its effects might last longer if you have mild to moderate ED. If you have any questions about the use of vardenafil, talk to your doctor.Vardenafil is in a class of medications called phosphodiesterase (PDE) inhibitors. It works by increasing blood flow to the penis during sexual stimulation. This increased . Vardenafil is used to treat men with erectile dysfunction (sexual impotence). It belongs to a group of medicines called phosphodiesterase 5 (PDE5) inhibitors. These . How does Viagra work? Viagra is used to treat erectile dysfunction (ED). It decreases ED symptoms by helping you get and keep an erection. Erections happen .