Walgreen has been dogged in the wake of its contract dispute with pharmacy benefit firm ExpressScripts (ESRX) which has caused a flood of customers to switch to rival pharmacies that were in ExpressScripts networks.
Walgreen became available to ExpressScripts clients as of Sept. 15, but that does not, however, mean all employers or health plan enrollees in ExpressScripts plans have to choose a Walgreen to fill their prescriptions.