Now here's something I didn't know. You don't have to join a wholesale club like Costco or Sam's Club in order to use their pharmacies (according to AARP author Janet Kinosian).
In a recent survey of the common generic drug, simvastatin, a thirty day supply ranged from $7.71 at Costco to $19.87 at an independent pharmacy. Wal-Mart charges $24.36. CVS gets $63.39 and Walgreens rakes in $89.99 for the same thing!
Call different drug stores to check current prices before purchasing your meds. And remember to check for harmful reactions and interactions.