While each PDE5 inhibitor differs slightly, they’re very similar in treating erectile dysfunction. Other conditions that may disqualify you from an ED prescription include a history of stroke, kidney or liver disease, cancer, diabetes, or a bleeding disorder. ED medications can cause side effects, and it’s crucial to have access to a medical provider if needed. This increase in blood flow results in a firmer, longer-lasting erection. As with sildenafil, a high-fat meal or alcohol keep the body from absorbing it as quickly. It works for up to 36 hours. It depends on the platform and insurance provider.AdSave Up to 80% on Prescriptions at Over 35, Pharmacies Nationwide with a Free Rx Coupon. Over 50K Customers Save on Prescriptions Each Week Using Free SingleCare® Discount : Maintenance, Accute, Branded, Generic. Sildenafil (Viagra). Tadalafil (Cialis). Vardenafil. These medicines are called PDE5 inhibitors. They enhance the effects of a chemical the body makes that relaxes muscles . Medically reviewed by Sophia Entringer, PharmD. Last updated on Uses Warnings Before taking Dosage Side effects Interactions FAQ What is Viagra? Viagra .