Getting a prescription from your doctor doesn’t mean you don’t have choices about how to spend your money.
Ask your doctor if a generic drug is available and make sure it’s in the same class of drugs as the expensive brand name drug he wants to you to buy.
Generics have the same active ingredients, strengths and dose as the more expensive brand name versions.
A single manufacturer no longer holds the (17 year!) patent, so there’s more competition to keep the price down.
Tell your doctor that if he wants you to have a brand name drug, then spend his money not yours! Or give you free samples.