Avanafil Stendra. Severe liver disease. Do not try to push the tablet through the foil. Before taking vardenafil, tell your doctor and pharmacist if you are allergic to vardenafil,any other medications. Oral medicine for ED also might not be safe or work well if you have: Very low blood pressure, called hypotension, or uncontrolled high blood pressure, called hypertension.No, vardenafil isn’t available over the counter (OTC). This is because it has some risks, like low blood pressure and painful erection, that your provider will want to . 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 . In fact, a recent review of studies found that some counterfeit drugs contained a very high, dangerous level of sildenafil that far exceeded a typical .