Part D is a federal prescription drug program put in effect to help Medicare recipients pay for their medications. Anyone who is currently enrolled in or eligible for Medicare Part A or Part B are already qualified to receive Plan D benefits in one of two ways; a Prescription Drug Plan or a Medicare Advantage Plan. Individuals can benefit from either plan, it just depends on the type of coverage needed.
A Prescription Drug Plan is just that. It only covers your prescription. This is completely separate from your Medicare health plan and can work together with another source, for example, retirement benefits or state pharmacy assistance programs.
The Medicare Advantage Plan is meant to work with your existing Medicare plan so you get your health benefits and prescription benefits in one package. This particular plan is actually associated with Medicare Part C and has other perks to it above your original Medicare plan.
With dozens of plans available within Part D, care should be taken in selecting the plan that’s right for you. Plans can vary on price of specific drugs, participating pharmacies, and cost of deductibles or copays. For instance, one plan may offer low copays on the drugs you use most but the pharmacy that you would need to use is 50 miles from you. Another plan may not offer low prices on all your medications but offers a lower deductible and is much closer to home. There are so many plans to choose from but one will definitely work for your needs.
As earlier stated, if you already are on or qualify for Part A or Part B, you are eligible for Part D. There are no physical exams to take and your current medication use does not matter. Income is not a factor in qualification, however, those who have an adjusted gross income at or above $80,000 (for singles) or $170,000 (for married filing joint) you will have a monthly surcharge anywhere from $12-$70. For those on a limited income there is help available to make your drugs affordable.
Which ever Medicare Part you currently are covered through, you will find Part D plan that is right for you.

[...] four main “parts”: They are Medicare Part A, Medicare Part B, Medicare Part C and Medicare Part D. This convenient segmenting allows you to pick and choose which “part” or [...]