A US prescription drug benefit program that was designed via Medicare Prescription Drug, Improvement, and Modernization Act of 2003. "D" means drugs. The program aims to subsidize the costs of prescription drugs and insurance premiums for beneficiaries. It gives three basic choices for recipients: stay in traditional Medicare without registering for the prescription drug benefit stated in the Act, remain in traditional Medicare, and sign up in a Medicare drug plan, other Medicare plans, or a comprehensive private health plan that can or cannot cover the prescription costs). The program started offering coverage on January 1, 2006.