5. What is the mail-order pharmacy service? Posted on September 11, 2017 at 12:45 pm.Written by advantage_admin It’s a service that allows you to order and receive your prescription drugs by mail. Triple-S Advantage offers its mail-order pharmacy service through Walgreens Mail Service. You can read more about it here (link to external page). Post navigation 3. How do I request a drug exception?2. What is the Medication Therapy Management Program?