<P> Medicare Part D, also called the Medicare prescription drug benefit, is a United States federal - government program to subsidize the costs of prescription drugs and prescription drug insurance premiums for Medicare beneficiaries . It was enacted as part of the Medicare Modernization Act of 2003 (which also made changes to the public Part C Medicare health plan program) and went into effect on January 1, 2006 . </P> <P> Individuals on Medicare are eligible for prescription drug coverage under a Part D plan if they are signed up for benefits under Medicare Part A and / or Part B. Beneficiaries obtain the Part D drug benefit through two types of plans administered by private insurance companies: the beneficiaries can join a standalone Prescription Drug Plan (PDP) for drug coverage only or they can join a public Part C health plan that jointly covers all hospital and medical services covered by Medicare Part A and Part B at a minimum, and typically covers additional healthcare costs not covered by Medicare Parts A and B including prescription drugs (MA - PD). (NOTE: Medicare beneficiaries need to be signed up for both Parts A and B to select Part C .) About two - thirds of all Medicare beneficiaries are enrolled directly in Part D or get Part - D - like benefits through a public Part C Medicare Advantage health plan . Another large group of Medicare beneficiaries get prescription drug coverage under plans offered by former employers . </P> <P> Generally, not all drugs are covered at the same out of pocket cost to the beneficiary . This gives participants incentives to choose certain drugs over others . This is most often implemented--as is the case for drug coverage for those not on Medicare--through incentives to use generic drugs over brand - name drugs . The incentive is also often implemented via a system of tiered formularies in which some brand - name drugs are less expensive than others and not subject to step therapy . </P>

What are the qualifications for medicare part d
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