Have kidney problems and require dialysis. What are the possible side effects of Levitra? A prolonged erection priapism can damage the penis. What should I tell my healthcare provider before taking Levitra? Have had an erection that lasted more than 4 hours.You should consult your health care professional before taking any drug, changing your diet, or commencing or discontinuing any course of treatment. Vardenafil is used to treat male sexual function problems (impotence or erectile dysfunction-ED). In combination with sexual stimulation, vardenafil w. Levitra is a prescription medicine taken by mouth for the treatment of erectile dysfunction (ED) in men. ED is a condition where the penis does not harden and expand when a man is sexually excited, or when he cannot keep an erection. A man who has trouble getting or keeping an erection should see his doctor for help if the condition . Find everything you need to know about Levitra (Vardenafil), including what it is used for, warnings, reviews, side effects, and interactions. Learn more about Levitra (Vardenafil) at.