NEW YORK (AP) -- A new report finds that prices for prescription drugs can vary greatly, meaning people could be overpaying if they don't do their homework.
Consumers Reports says it compared drug prices for five blockbuster drugs that recently went generic and found that Costco (NASDAQ: COST ) offered the lowest prices overall and CVS Caremark (NYSE: CVS ) charged the highest.
The group said its "secret shoppers" called more than 200 pharmacies in the U.S. to get retail prices, which is the amount people pay without insurance, for a month's supply of five drugs -- Actos, for diabetes; Lexapro, an antidepressant; Lipitor, for high cholesterol; Plavix, a blood thinner; and Singulair, for asthma.
The differences could be significant. For example a month's supply of the generic version of Lipitor cost $17 at CostCo but was $150 at CVS. A month's supply of generic Lexapro was $7 at CostCo and $126 at CVS.
A representative for CVS did not immediately respond to a request for comment.
Consumer Reports noted that prices varied greatly at local, independent pharmacies, but that such outlets could have competitive prices as well.
The broader differences in price are partly because retailers have varying business models, according to Consumer Reports. For example, big-box retailers might use their pharmacies as a way to attract shoppers, who spend on other items as well.