Mandatory Mail program - These benefits include a mandatory mail delivery program for certain covered maintenance drugs. These drugs are shown on the Blue Cross Blue Shield Maintenance Drug List. When the member buys any one of these maintenance drugs from a retail pharmacy, this health plan provides retail pharmacy benefits for up to two fills of the same drug within a 180-day period. For additional fills of the same maintenance drug within this period, coverage is available only when the member buys that drug from the designated mail service pharmacy. To find out which drugs are included on the approved Maintenance medication list, the member may call the Blue Cross Blue Shield customer service office.