Vardenafil usually works for 4 to 5 hours. This medication is taken with or without food an hour before sex. They’re often the first line of treatment for trouble getting or keeping an erection, called erectile dysfunction ED. Medicines that you take by mouth are called oral medicines. As with sildenafil, a high-fat meal or alcohol keep the body from absorbing it as quickly. If it is not treated right away, priapism can permanently damage your penis sudden vision loss in one or both eyes.Viagra. Compare prices and print coupons for Sildenafil (Generic Revatio and Viagra) and other drugs at CVS, Walgreens, and other pharmacies. Prices start at $ Oral medicines for ED usually work well and cause few side effects. The four main medicines taken by mouth for erectile dysfunction are: Avanafil (Stendra). Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. 1 day ago · How we vet brands and products. If you’re interested in buying Viagra online, five of the best options available are Hims, Roman, Lemonaid, Optum Store, and REX MD. Read on for full details on.