You already know that the cost of your prescriptions can vary widely from retailer to retailer.

But maybe you think the price difference is a wash when you use a discount pharmacy card.

Well, we’ve got bad news for you. It’s still possible to overpay by hundreds of dollars even when you’re using a discount card!

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You’ve still got to comparison shop for medicine

The New York Post recently ran an article that showed discount pharmacy cards are anything but the great equalizer of pricing. You may think that a discount card brings prescription prices from various retailers into the same orbit for both the uninsured and those who have lousy insurance.

But you’d be wrong…

In fact, the prices for the same drug in the same dosage can be all over the place when you use a discount pharmacy card. Check out these prices, which are all based on using the discount card from ScriptSave WellRx:

• Walmart sells a “discounted” 30 mg fill of 30 Crestor pills for $238.24. Walgreens/Duane Reade, meanwhile, prices out at $74.34 for the same scrip!
• Rite Aid will charge you $27.20 for Lunesta with your discount card. But Walgreens/Duane Reade will charge you $100.59.
• A generic of Flonase can be had for $11.01 at Safeway with your card. Kroger, meanwhile, charges more than three times as much.

Those companies that offer discount drug cards use prescription volume to negotiate discounts with the drug manufacturers. So you typically pay less when using them at a retail outlet.

They also make money on transaction fees, industry insiders tell the Post.

But the price of drugs may change everyday with these cards. So, if money is important to you, you’ve still got to comparison shop even when you plan to whip out your card at the register.

Free apps like GoodRx and LowestMed will let you easily search nearby pharmacies for discounts and coupons that you didn’t know existed.

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How to comparison shop your prescriptions