In the United States, Viagra is a prescription-only medication. A prescription from a healthcare provider is required to purchase brand-name and generic Viagra online. You can obtain a Viagra prescription from a healthcare provider in person or online through a reputable telehealth company. If you choose to go the online route, a healthcare provider will evaluate your health conditions and other medications during an online consultation to see if an ED drug is right for you. With a valid prescription, you can buy Viagra online from a licensed online pharmacy.