One of the dirty secrets of the prescription drug market is many common prescription drugs are dirt cheap.
A few months ago, Walmart began offering a 30 day supply of many common generics for $4 for a 30 day supply. Since I despise Walmart, I am happy to report Target has matched the offer.
If you have a common 10 retail or $20 mail-in copay, it is cheaper to buy a 90 day supply without using insurance. Just make sure you get credit toward your deductible.