HERE is a link to the Walgreens coupon policy. Print it out and take it with you every time you go! It will save you a headache or two!!!
Walgreens has the Register Rewards (RR) program. You will notice in their weekly add that they have certain items that when purchased, will give you RR for your next purchase. This helps you save extra money. Walgreens will eccept one Walgreen coupon (in add coupon) and one manufacturers coupon (MC) for each item. The RR are essentially MCs. If you have MCs for each of the items you are purchasing, the register will not allow you to add the RR. You will need to add a "filler" item to be able to use the RR.
Walgreens also comes out with Monthly coupon booklets that you can get in store. You can use one of these coupons along with a MC but not with another store coupon.
When you go to the register make sure you give the clerk all of your MC's before you give them the in ad or in store coupons.