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. A phone or video consultation is sometimes required for legal purposes. Common side effects include headache, facial flushing, indigestion, and dizziness. And not all online pharmacies have the capability to safely ship medications that need to be temperature-controlled, such as insulin. Medical consultations were also taken into consideration, as PDE5 inhibitors require a valid prescription from a licensed medical provider. Generic vs.Sildenafil is used to treat male sexual function problems (impotence or erectile . If you’re interested in buying Viagra online, five of the best options available are Hims, . Amazon Pharmacy: Sildenafil (Generic for Viagra, Oral Tablet).us. Account Returns& .