The active component in Zudena tablets is Udenafil. It belongs to the group of drugs called PDE5 inhibitors. To treat erectile dysfunction, use a 100mg Zudena pill. It works by relaxing the blood vessels, allowing blood to flow into the genitals when aroused. It should be consumed 45 to 60 minutes prior to the event. The tablet in this medication is designed to remain active in the blood plasma for roughly 24 hours. Zudena 100mg pills are available in a box with a strip of four tablets.