What is a drug list or formulary?

Most Medicare Part D plans will have a formulary, which is the list of drugs the plan covers. Each plan will publish its formulary on its website. The Medicare.gov Prescription Drug Plan Finder shows you:

  • If the plan covers your drugs.
  • The tier or level each drug is on, which tells you how much the drug will cost.  A lower tier will have a lower cost.  Instead of showing a tier for each drug, some formularies will tell you whether a drug is “approved” or “preferred.”
  • If there are any special rules or limits on how you can buy the drug.

Which drugs will be covered, and on the drug list?

Medicare has developed basic guidelines about plan formularies. They must  cover  drugs that are used to treat common conditions. They also must have at least two drugs from each type or class of drugs. Medicare has reviewed and approved each plan's drug list.

Formularies will include generic and brand name drugs.

“Brand name” drugs - When the U.S. Food and Drug Administration approves a drug for the first time, there is only one manufacturer who makes and sells that drug under their patent. New drugs get to be known by the brand name. These are referred to as “brand name drugs” until their patent expires.

“Generic” drugs - A generic drug can be produced after the brand name drug's patent has expired.  It is also called a “generic equivalent.”  Before a generic drug can be sold, the U.S. Food and Drug Administration must approve its use. If you follow the directions on the drug’s label, the generic and the brand name drug should have the same effects, safety and risks.

My drug plan’s formulary changed in the middle of the year. Is that allowed?

Part D plans sometimes change their formularies during the course of the year. This happens because new drugs come on or are taken off the market, or generic versions of a brand name drug become available, or when there are new clinical guidelines about the use of a medication. Part D plans are required to provide 60 days' notice to all plan members about a formulary change before it happens.

How do I get information about my plan’s drug list?

Each Medicare Prescription Drug Plan is required to post its formulary on its website and update it each month. You can also find information about drug lists on the Medicare.gov Plan Finder.

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