What Medicare Part D Covers

Medicare Part D plans cover your prescription medications. They are offered by private insurance carriers that Medicare has approved. Each Part D plan has a list of medications it covers, called a drug formulary. It is broken down into tiers, with most plans having four or five tiers.

What Does Medicare Part D Cover?

Each Medicare Part D plan has a drug formulary, which is a list of all the drugs it covers. The federal Medicare program requires that all plans offer at least two drugs in each category, Also, each plan must cover all prescriptions used for the following purposes:

  • Antidepressants
  • Antipsychotics
  • Anticonvulsants
  • Anti-cancer
  • Immunosuppressants

Part D plans must also cover vaccines used to prevent illnesses unless those vaccines already fall under Part B coverage.


Medicare Part D covers these certain drugs.

What Drugs Are Not Covered by Part D?

Some prescriptions are covered by Part B of Original Medicare. If your doctor has to administer the medication or it’s an intravenous drug, it’s likely covered under Part B instead of Part D.

In addition, Part D does not cover any over-the-counter (OTC) medications like ibuprofen, Tylenol, or cough syrup. Other drugs not covered by Part D include:

  • Any weight loss or weight gain drugs
  • Fertility medication
  • Erectile dysfunction medications
  • Hair loss prevention drugs
  • Other cosmetic medications

Of course, every Part D plan is different, and you may find one that offers coverage for some of these things. However, that’s not the norm.

If you need a prescription that isn’t covered by your plan, you may be able to ask for an exception. Your doctor will need to fill out a form stating why you need the medication and why alternative treatments are not an option. Exceptions also apply when your doctor states you need a drug in a higher tier versus an alternative offered in a lower tier. You can file an exception to get the more expensive drug at the lower-tier price. Neither of these scenarios is a guarantee that your plan will make an exception, but it is certainly worth trying!

Many plans also use a requirement called step therapy. If a prescription requires step therapy, that will be noted on the plan’s drug formulary. Step therapy is a process insurance companies use to try to keep their costs (and yours) as low as possible. It requires you to try other (cheaper) medications before approving the one your doctor prescribed.

If you’ve tried all options to get your prescription covered by your plan and nothing has worked, another option is to consider a prescription discount program or drug savings program. There are many of these available, and most of them are completely free to use.

Options like GoodRx, Cost Plus Drugs, Blink Health, SingleCare, and Optum Perks, as well as other discount programs offered directly from your local pharmacy, are all great ways to save money on prescriptions. You can even choose to use these instead of your Part D plan if you find that it offers better coverage than your plan does.


A Word on Generic Medications

Probably the best way to control your prescription costs is to take generics whenever possible. Using generic medications will decrease your coinsurance amount and prolong your coverage before falling into the Medicare donut hole.

The Food and Drug Administration (FDA) states that generic drugs must be identical to their name-brand counterparts in dosage, safety, strength, quality, administration route, performance, and intended use. They must have the same active ingredients and must work the same way as the name-brand version.

Not all name-brand medications have generic options. However, there could be a generic alternative to a similar drug. Chat with your doctor or healthcare provider about switching to a generic option to save on prescription costs.

Part D Formulary Changes

It’s important to realize that drugs can come and go from the formularies at any time. However, the insurance carrier must let you know when any changes are coming.

All plans are restricted from making changes to the covered drugs or making price changes between the beginning of the Annual Election Period (AEP) and 60 days after coverage begins. The only exception is if the Food and Drug Administration determines a drug is unsafe or if the drug manufacturer quits producing it.

The manufacturer must tell you which drug is being removed, if there is a tier change, the reason for any changes, alternative drugs available, cost-sharing changes, and any exceptions.



Annual PDP Reviews are important.

Of course, most plans make changes to their formularies and premiums each year. Part D plans operate on annual contracts, so you’ll often see significant changes from one year to the next. For this reason, we always recommend our clients review their Medicare plans during the Annual Election Period.

AEP begins on October 15 and lasts until December 7. During this time, you can shop for other Part D plans. If you make any changes, the new plan goes into effect on January 1 of the upcoming year.

It’s important to review your plans during AEP as there could be changes that negatively impact your benefits or your costs. It may be that the plan will no longer cover one of your medications or that the price is increasing. Take a few minutes to review your plan with Bobby Brock Insurance to ensure you have the best Part D plan for you.

Talk to an expert.


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