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What is a Medicare Part D Prescription Drug Plan Formulary

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If you have a chronic illness, taking regular prescription drugs may be an important part of maintaining your health. Since Original Medicare (Part A and Part B) doesn’t cover most prescription drugs you take at home, many Medicare beneficiaries look to Medicare Part D administered through private insurance companies.

Medicare Part D is prescription drug coverage for Medicare beneficiaries. You can get Medicare Part D coverage through either a stand-alone Part D plan to go alongside Original Medicare (Part A and Part B) or through a Medicare Advantage plan with prescription drug coverage.

Both Medicare Advantage plans and stand-alone Medicare Part D Prescription Drug Plans have formularies. A Medicare Part D formulary is simply a list of covered prescription drugs and vaccines. The formulary may change at any time, but your plan will notify you when necessary. Formularies can differ form plan to plan, but Medicare dictates some medications that all Medicare Part D formularies must cover.

What prescription drugs are covered by all Medicare Part D formularies?

Part D plans must also cover all or substantially all:

  • Immunosuppressants (to prevent organ transplant rejection)
  • Antidepressants (to treat depression)
  • Antipsychotics (to treat mental health disorders)
  • Anticonvulsants (to treat seizures)
  • Antiretrovirals (to treat HIV/Aids)
  • Antineoplastics (to inhibit growth and spread of precancerous cells, cancer cells, or tumors)

According to the Centers for Disease Control and Prevention (CMS) these drugs must be covered to “mitigate the risks and complications associated with an interruption of therapy for these vulnerable populations.”

Medicare Part D Formularies also generally cover all commercially available vaccines as long as the vaccine is reasonable and necessary to prevent illness and not already covered by Medicare Part B. This includes the shingles vaccine, for example.

What prescription drugs are excluded from all Medicare Part D formularies?

A non-exhausting list of prescription drugs excluded from Medicare Part D formularies include:

  • Medications for weight loss or weight gain
  • Medications for cosmetic purposes or hair growth
  • Medications for symptomatic relief of cough and colds
  • Prescription vitamins and minerals (except prenatal vitamins and fluoride preparations)

Medicare Part D formularies also generally don’t cover over the counter (OTC) medications such as Tylenol and Advil.

What if my prescription drug is not covered by my Medicare Part D formulary?

If your prescription drug is not on your Medicare Part D formulary, you may have to pay for that prescription drug out of pocket. Your other options are to:

  • Switch Medicare Advantage or Medicare Part D plans to one that does cover your medication. You can do this during the Open Enrollment Period October 15 to December 7 each year.
  • Appeal the coverage decision. According the Centers for Medicare and Medicaid Services (CMS) you have the right to ask your plan to pay for a prescription drug you think should be covered, provided, or continued. Working with your provider, you can ask for an exception. Learn more about Medicare appeals.

What are the Medicare Part D formulary tiers?

Medicare Part D formulary tiers are ways to organize medications by price. The amount you pay for a prescription drug may depend on which tier your drug is on. A Medicare Part D formulary may categorize prescription drugs into five tiers:

  • Tier 1– preferred generic: These are the prescription drugs that typically have the lowest cost share for you.
  • Tier 2 – generic: These prescription drugs usually have a higher cost share than tier 1 drugs.
  • Tier 3 – preferred brand: These prescription drugs are higher in cost than tier 2
  • Tier 4 – non-preferred drugs: these prescription drugs are sometimes higher in cost than tier 3
  • Tier 5 – specialty: these are the highest cost drugs, including some injectables
  • Tier 6 – Select care drugs: the copayment may actually be lower than tier 1 drugs

Your plan might let you know when your prescription drug is moved to a higher cost-sharing tier.

Do you have any questions about your Medicare Part D formulary tiers? Feel free to enter your zip code on this page to browse Medicare plan options in your area .

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