Drugs such as Viagra (Sildenafil), Vidalista (Cialis Tadalafil ) and Levitra belong to the group of PDE5 inhibitors used to treat erectile dysfunction. They dilate blood vessels and improve blood flow to the penis during sexual stimulation . This achieves and maintains a firm erection and helps to enjoy penetrative intercourse. According to statistics, these drugs are effective in treating ED in about 80 percent of all patients.
