Prescription Drug Plans (PDP)  are plans provided by private insurance companies approved by the federal government.  They help pay for the prescription drugs that your doctor prescribes.  Medicare Part D can be purchased as a standalone Medicare PDP with Part A and Part B or as part of a Medicare Advantage Plan, or with a Medicare Supplement plan. Medicare Part D plans should be purchased when you first become eligible for Medicare, even if you are currently not taking prescription drugs.  If no Prescription Drug Plan is purchased within 63 days of starting Medicare, a Late Enrollment Penalty could be charged for every month you go without "creditable coverage" or are receiving "Extra Help".  Once assessed, this penalty is charged monthly for as long as you have a Prescription Drug Plan.  If you are currently taking medications it is important to check the plans' formularies for the cost of your prescriptions and that your pharmacy is preferred for the plan. 


Each Prescription Drug Plan and Medicare Advantage Plan that includes drugs have a list of medications that are covered called a Formulary.  The Formulary will include both generic and brand name drugs but not all formularies include all medications.  It is important that you review the plans to ensure that your medications are included in the formulary.  If you are taking a medication that is not in the plan's formulary, you will have to pay full price for the medication. Formularies are made of tiers.  Costs differ for each tier, usually the lower the tier, the lower the cost.  The tiers usually range from Generic to Brand Name and Specialty Drugs.  Most plans have a deductible for the higher tiers so in other words you will pay the full cost of the medication in a higher tier until the deductible is met.  Deductibles normally do not apply to lower tier medications.