Insurance: If you plan to use insurance, make sure the online provider accepts it. Often, these are prescribed for chest pain called angina. Oral ED medicines might not work or might be dangerous if you also take any of the following: Nitrate medicines. It depends on the platform and insurance provider. We considered cost, medications available, and whether generic versions were offered to help reduce costs.You can’t get Viagra over the counter in the USA (at present). All doses of it need a prescription from a practitioner. This is because a healthcare professional will need to check that it’s safe for you before you use it. Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. They enhance the effects of a chemical the body makes that relaxes muscles in the penis, called nitric oxide. This boosts blood flow and helps you get an erection from sexual activity. How oral medicines differ. Extra 15% off $30 sitewide with code SAVE15; Clip your mystery deal! BOGO 50% off select Walgreens health & wellness.