If you do not have insurance to pay for the drugs no prescription coverage or you risk falling into the Medicare doughnut hole : Begin by comparing drug prices at one of the sites that help you make that comparison. The mechanism of action for ED pills is simple: They inhibit the PDE5 enzyme which regulates the signals responsible for the smooth muscle tissue. Cialis tadalafil : This ED medication works with the same principle as Viagra, but lasts up to 36 hours. Local drug stores have sites; you may be able to use one to fill or renew a prescription. Also, look into whether expediting is offered. Your primary care doctor should always know what medications you’re taking, including ED pills prescribed by another provider.If you do buy medicines over the internet: Check to see if an online pharmacy is legitimate. Never order medicines from an online pharmacy that doesn’t list its phone number and physical address, has prices that seem too good to be true, or tells you that no prescription is needed. According to price-comparison site , generic Revatio will cost you as little as $ per pill, depending on where you fill your prescription. That’s compared with more than $50 per. 1 day ago · If you’re looking for convenience or discretion while shopping for Viagra online, you will first need a prescription. Thankfully several telehealth companies, such as Hims, Roman, Lemonaid.