Here is the link to the coupon.

Note that this coupon states that your total must still be $20 AFTER all coupons. Bummer. Those marketing folks are getting smart, because it used to be that we could use that coupon first, then use some mfr coupons to get your total next to $0.

But there is still a bit of money to made, if you think you’re going to start shopping at Walgreen’s frequently. Get the monthly booklet at the front of the store and turn to page 38. There you will find the tally sheet for the monthly rebates. Notice that the first few items are free after rebate. Find some items you like or can use, and purchase $20 worth of those items. Then, hang on to your receipt and send in the rebate request. Instead of requesting a check, request a gift card–they will increase your amount by 10%.

So your transaction will look like this:
$20 worth of Free after Rebate items
-$5 coupon
Pay $15 + tax
Request rebate in form of gift card, and you’ll receive
$20 + 10%, or $22 in a gift card.

After you receive your $22 gift card, you can begin ‘rolling’ it into RR deals and other rebate deals.