The most common symptoms of erectile dysfunction include difficulty achieving or maintaining an erection and reduced sexual desire. Both options require valid medical documentation, but some online services only require a health questionnaire to be filled out and reviewed for approval—meaning no face-to-face video interaction is needed. Cialis Daily tadalafil : This low-dose Cialis works by increasing blood flow to the penis over time, making it easier to have an erection when aroused. Levitra vardenafil : This medication is taken one hour before sex and can last up to 24 hours. These include a heart attack, stroke or a serious heart rhythm disorder in the past six months.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 . It’s no longer sold under the brand name Levitra, but it’s available as generic tablets and orally disintegrating tablets (ODTs). Common side effects of vardenafil Missing: online shop. Here’s the easiest way to use GoodRx to get Levitra cheaper: Download the GoodRx app on your mobile device. Search for Levitra or vardenafil in the app (or by Missing: online shop.