If you have health insurance and do not want to be stuck with an unexpected bill, make sure to call your insurance company before making an appointment to confirm your doctor is covered under your plan. Payment options: Consider how you’d like to pay. You don’t need a health insurance plan to purchase Viagra, but prescriptions are usually cheaper with one. Refills: See if you can set up automatic refills or order as needed. That’s not to say there aren’t just as many illegitimate sites.Make sure you get the right prescription and dose. When you order medicines and when you receive them in the mail, make sure they’re the exact dose and type prescribed by your doctor or other health care professional. The dose is the amount of medicine you take. Don’t be fooled into buying “herbal viagra.”. And while generic Revatio is available only in a mg strength—Viagra comes in , , and mg tabs—not to worry: Your doctor can prescribe the most appropriate equivalent dose. Many medical clinics now offer remote health services where you can request a prescription online without visiting a doctor in person. Many online companies claim to sell Viagra without a.