Walgreens is now running its first Foursquare promotion to promote “Friends and Family Day”. In addition to Foursquare, the promotion is being pushed via other social avenues, such as Facebook, Twitter and SMS list-services. When Walgreens’ customers visit a local store and check-in on Foursquare, Walgreens will provide them with 15% off of select items and 20% off of Walgreens-brand items. Walgreens currently has 35,000 Foursquare followers. To read more about the promotion, visit ClickZ.com.