Do not keep outdated medicine or medicine no longer needed. Do not use any other medicine to treat impotence unless your doctor tells you to. This medicine should come with a patient information leaflet. What should I do if I missed a dose of Levitra Vardenafil? Allow 24 hours to pass between doses. · Adults up to 65 years—10 mg as a single dose, no more than once per day, approximately 1 hour before sexual activity. Your doctor may adjust your dose if needed. . Hearing loss or ringing in ears. Heart attack—pain or tightness in the chest, shoulders, arms, or jaw, nausea, shortness of breath, cold or clammy skin, feeling faint or lightheaded. . 5 milligrams 10 milligrams 20 milligrams The best dose depends on your: age health medications Dosages Levitra is available as an oral tablet in several strengths. .