Medicare Prescription Drug Plan (Part D). These plans (sometimes called "PDPs") add drug coverage to Original Medicare, some Medicare Cost Plans, some Medicare Private Fee-for-Service (PFFS) Plans, and Medicare Medical Savings Account (MSA) Plans.
Each Medicare Prescription Drug Plan has its own list of covered drugs (called a formulary). Many Medicare drug plans place drugs into different "tiers" on their formularies. Drugs in each tier have a different cost.
A drug in a lower tier will generally cost you less than a drug in a higher tier. In some cases, if your drug is on a higher tier and your prescriber thinks you need that drug instead of a similar drug on a lower tier, you or your prescriber can ask your plan for an exception to get a lower copayment.
